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Class XP^Xi 

Book Q_53_ 

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COPYK1G11T DEPOSIT. 



GAS AND FUEL ANALYSIS 
FOR ENGINEERS. 



A COMPEND FOR THOSE INTERESTED IN THE 
ECONOMICAL APPLICATION OF FUEL. 



PREPARED ESPECIALLY FOR THE USE OF STUDENTS 

at the 
MASSACHUSETTS INSTITUTE OF TECHNOLOGY. 



BY 

AUGUSTUS H. GILL, S.B., Ph.D., 

Associate Professor of Technical Analysis at the 

Massachusetts Institute of Technology, Boston, Mass, 

Author of " A Short Handbook of Oil Analysis" 




FOURTH EDITION, REVISED. 
FIRST THOUSAND. 



NEW YORK: 

JOHN WILEY & SONS. 

London: CHAPMAN & HALL, Limited. 

1907. 



f 



f3 






LIBRARY of CONGRESS 
Two Cooies Received 

MAR 14 1907 

a Copyright Entry 
yClASS A XXc„Nb. 
COPY B. 



Copyright^ 1896, 1902, 1907, 



BY 



AUGUSTUS H. GILL. 



i?~lWtf 



ROBERT DRUMMOND, PRINTER, NEW YORK. 



PREFACE. 



This little book is an attempt to present in a con- 
cise yet clear form the methods of gas and fuel analy- 
sis involved in testing the efficiency of a boiler plant. 
Its substance was given originally, in the form of 
lectures and heliotyped notes, to the students in the 
courses of Chemical, Mechanical, and Electrical En- 
gineering, but in response to requests it has been 
deemed expedient to give it a wider circulation. 

At the time of its' conception, nothing of the kind 
was known to exist in the English language ; in 
German we now have the excellent little book of Dr. 
Ferdinand Fischer, " Taschenbuch fur Feuerungs- 
Techniker." 

The present book is the result of six years' experi- 
ence in the instruction of classes of about one hun- 
dred students. It is in no sense a copy of any other 
work, nor is it a mere compilation. The author has 
in every case endeavored to give credit where any- 
thing has been taken from outside sources; it is, how- 



111 



IV PREFA CE. 

ever, difficult to credit single ideas, and if he has 
been remiss in this respect it has been unintentional. 

The study of flue-gas analysis enables the engineer 
to investigate the various sources of loss ; and if this 
compend stimulates and renders easy such investiga- 
tion, the writer's purpose will have been accomplished. 
The necessary apparatus can be obtained from the 
leading dealers in New York City. 

The author wishes to acknowledge his indebtedness 
to our former Professor of Analytical Chemistry, Dr. 
Thomas M. Drown, and to Mrs. Ellen H. Richards, 

by whose efforts the department of Gas Analysis was 
established. 

He will also be grateful for any suggestions or cor- 
rections from the profession. 

Massachusetts Institute of Technology, 
Boston, November, 1896. 

PREFACE TO THE THIRD EDITION. 

The increasing use of gaseous fuel has made it 
necessary to add a chapter on Hempel's apparatus 
for its analysis. The methods for the analysis of 
solid fuels have been revised to conform to those 
lately adopted by the American Chemical Society, 
and a description * of the Parr coal-calorimeter in- 
cluded, i 

Minor additions and corrections have been made 
so as to bring the book up to present practice. 

Massachusetts Institute of Technology, 
April, 1902. 



CONTENTS, 



CHAPTER I. PAGE 

Introduction. Sampling — Sampling-tubes. Suction Appa- 
ratus. Gas-holders i 

CHAPTER II. 

Apparatus for the Analysis of Chimney-gases. Appa- 
ratus of Orsat, Bunte, and Elliott n 

CHAPTER III. 
The Measurement of Temperature. Thermometers — Le 

Chatelier Pyrometer — Metals and Salts 25 

CHAPTER IV. 

Calculations. " Pounds of Air per Pound of Coal," and 
Percentage of Heat Carried off by the Flue-gases. Loss 
due to Formation of Carbonic Oxide. Loss due to Un- 
consumed Fuel 28 

CHAPTER V. 

Apparatus for the Analysis of Fuel and Illuminating 

Gases. Apparatus of Hempel 35 

CHAPTER VI. 

Preparation of Reagents and Arrangement of the 

Laboratory 49 

CHAPTER VII. 

Fuels, Solid, Liquid, and Gaseous : their Derivation 

and Composition 56 

CHAPTER VIII. , 
Fuels. Methods of Analysis and Determination of the 
Heating Value. Determination of the Various Constit- 
uents. The Mahler Bomb, the Parr Coal-calorimeter, 
and Junkers Gas-calorimeter 67 

APPENDIX. 

Tables 100 

r iii 



LIST OF ILLUSTRATIONS. 



FIG. PAGE 

1. Gas Sampling-tube •••• 3 

2. Sampling Apparatus •• 4 

3. Sampling Apparatus for Mine-gases ....... 5 

4. Gas-tube 5 

5. Richards's Jet-pump 8 

6. Bunsen's Pump 8 

7. Steam Air-pump 9 

8. Orsat Gas Apparatus . , 12 

9. Bunte Gas Apparatus 17 

10. Elliott Gas Apparatus 21 

n. Melting-point Boxes 27 

12. Hempel Gas Apparatus 36 

13. Hempel Gas Apparatus 37 

14. Muencke's Aspirator 54 

15. Combustion-furnace 69 

16. Mahler Bomb . 76 

17. Mahler Bomb and Calorimeter 77 

18. Parr's Calorimeter 86 

19. Junkers Gas-calorimeter, section 91 

20. Junkers Gas-calorimeter 92 

v 



GAS AND FUEL ANALYSIS, 



CHAPTER I. 
INTRODUCTION AND METHODS OF SAMPLING. 

UNTIL within recent years, the mechanical engineer 
in testing a boiler plant has been compelled to con- 
tent himself with the bare statement of its efficiency, 
little or no idea being obtained as to the apportion- 
ment of the losses. Knowing the composition and 
temperature of the chimney-gases and the analysis of 
the coal and ash, the loss due to the formation of car- 
bonic oxide, to the imperfect combustion of the coal, 
to the high temperature of the escaping gases, can 
each be determined and thus a basis for their reduc- 
tion to a minimum established. 

By the simple analysis of the chimney-gases and 
determination of their temperature, a very good idea 
of the efficiency of the plant can be obtained previous 
to making the engineering test. For example, in a 
test which the author made in connection with his 
students, the efficiency was increased from 58 to 70 
per cent, upon the results of the gas analysis alone. 



2 GAS AND FUEL ANALYSIS, 

To this end a representative sample must be collected 
according to the method about to be described. 

SAMPLING. 

Before proceeding to take a sample of the gas, the 
plant — for example, a boiler setting — from which the 
gas is to be taken should be thoroughly inspected, 
and all apertures by which the air can enter, carefully 
stopped up. A suitable tube is then inserted air-tight 
in the gas-duct, connected with the sampling or gas 
apparatus, and suction applied, thus drawing the gas 
out. Cork, putty, plaster of Paris, wet cotton-waste, 
or asbestos may be used to render the joint gas-tight. 
The place of insertion should be chosen where the gas 
will be most completely mixed and least contaminated 
with air. The oil-bath containing the thermometer is 
similarly inserted near the gas-tube, and the tempera- 
ture read from time to time. 

I. Tubes. — The tubes usually employed are Bohe- 
mian-glass combustion tubing or water-cooled metal 
tubes; those of porcelain or platinum are also some- 
times used. Glass and porcelain tubes when subjected 
to high temperatures must be previously warmed or 
gradually inserted: the former may be used up to 
temperatures of 6oo° C. (1200 F.). Uncooled metal 
tubes, other than those of platinum, should under no 
circumstances be used.* 



* Fischer, " Technologie der Brennstoffe," 1SS0, p. 221, states 
that the composition of a gaseous mixture was changed from 1.5 
to 26.0 per cent carbon dioxide, by the passage through an iron 
tube heated to a dull red heat, the carbonic oxide originally 
present reducing the iron oxide with the formation of carbon 
dioxide. 



INTRODUCTION AND METHODS OF SAMPLING. 3 

The metal tube with the water cooling is made as 
shown in Fig. I, c being a piece of brass pipe 3 
feet long, \\ inches outside diameter, b the same 
length, I inch in diameter, and a \ inch in diameter. 
The water enters at d and leaves at e. The walls of 



e 

e 



I 



a 



" .1 ^ ■--■- ■! ■ 1*11 * • » 




Fig. i.— Gas-sampling Tube. 

the tubes are T ^ inch thick. The joint at A should 
be brazed; the others may be soldered. 

Platinum tubes from their high cost and small bore 
are seldom used ; they are attacked by carbon, cyan- 
ogen, arsenic, and metallic vapors. 

2. Apparatus for the Collection of Samples.— 
A convenient sampling apparatus is shown in Fig. 2. 
It may be made from a liter separatory funnel — in- 
stead of the bulb there shown — fitted with a rubber 
stopper carrying a tube passing to the bottom and a 
T tube; both of these, except where sulphur-con- 
taining gases are present, can advantageously be 
made of T \-inch lead pipe. The stopper should not 
be fastened down with wire between the tubes after 
the manner of wiring effervescent drinks, as this 
draws the rubber away from the tubes and occasions 
a leak. The fastening shown consists of a brass plate 
fitting upon the top of the stopper, provided with 
screws and nuts which pass through a wire around 



GAS AND FUEL ANALYSIS. 



the neck of the separatory. A chain fastened to the 
plate serves as a convenient method of handling it. 

In using the apparatus, the bulb is filled with water 
by connecting the stem with the water-supply and 
opening one of the pinchcocks upon the T tube; the 




Fig. 2.— Sampling Apparatus. 

water thus entering from the bottom forces the air 
out before it. One branch of the T is connected with 
the sampling-tube and the other with the suction- 
pump, the stopcocks being open, and a current of gas 
drawn down into the pump; upon opening the cock 
upon the stem, the water runs out, drawing a small 
portion of the gas-current passing through the T after 
it into the bulb. It is then taken to a convenient 



INTRODUCTION AND METHODS OF SAMPLING. $ 

place for analysis, the tube h connected with a head of 
water, a branch of the T i, with the gas apparatus, and 
a sample of gas forced over into the letter for analysis. 




Fig. 4.— Gas-tube. Fig. 3.— Sampling Apparatus for 

Mine-gases. 

Enough water should be left in the bulb to seal the 
stopcock on the bottom and prevent leakage. This 
apparatus is better adapted for the needs of the class- 



6 GAS AND FUEL ANALYSIS. 

room than for actual practice, as it enables the same 
sample to be given to eight or ten students. As has 
been shown by several years' experience, the water 
exercises no appreciable solvent action upon the 
gaseous mixture in the time — about half an hour — 
necessary to collect and distribute the samples. It is 
often necessary to attach about a yard of ^-inch 
rubber tubing to the stem of the bulb to prevent air 
being sucked up through it when taking a sample. 

In the actual boiler-test it is preferable to insert a 
T instead of this apparatus in the gas-stream, connect 
the gas apparatus to the free branch of this T, and 
draw the sample. In making connections with gas 
apparatus the air in the rubber connectors should be 
displaced with water by means of a medicine- 
dropper. 

In the Saxon coal-mines, zinc cans of ten liters 
capacity, of the form shown in Fig. 3, are used by 
Winkler for sampling the mine-gases; they are carried 
down filled with water and this allowed to run out, 
and the gas thus obtained brought into the laboratory 
and analyzed. Small samples of gas may very well be 
taken in tubes of 100 cc. capacity like Fig. 4, the 
ends of which are closed with rubber connectors and 
glass plugs. Rubber bags are not to be recommended 
for the collection and storage of gas for analysis, as 
they permit of the diffusion of gases, notably hydro- 
gen. 

3. Apparatus for Producing Suction. — I. Water- 
pumps — (a) Jet- pumps, depending for their action 
upon a considerable head of water, and (b) those 
depending rather upon a sufficient fall of water. 



INTRODUCTION AND METHODS OF SAMPLING. 7 

{a) Jet-pumps. — The Richards' jet pump* is shown 
in section in Fig. 5 and much resembles a boiler 
injector; it consists of a water-jet w, a constriction or 
waist a, a waste-tube o, and a tube for the inspiration 
of air. The jet of water forms successive pistons 
across a, drawing the air in with it and is broken up 
into foam by the zigzag tube o. 

This pump is known in Germany as Muencke's, and 
in England as Wing's; Chapman's pump is also a 
modified form. 

It may be easily constructed in glass, the jets pass- 
ing through rubber stoppers which are wired down, 
thus admitting of adjustment to the conditions under 
which it has to work.f 

(b) Fall-pumps. — Bunsen's pump, Fig. 6, consists 
of a wide glass tube A, drawn out at the bottom for 
connection with a J-inch lead pipe b, and at the top 
for connection with c, the tube through which the air 
is drawn; this tube is usually fused in, although it 
may be connected with rubber; a is a rubber tube 
provided with screw cocks connected with the water- 
supply; d is connected with a mercury column, and 
the vessel B serves for the retention of any water 
which might be drawn back into the apparatus evac- 
uated. 

The tube b for the best results should be 32 feet in 
length, equal to the height of a column of water sup- 
ported by the atmosphere, although for the ordinary 
purposes of gas-sampling it may be shorter. 

When water is admitted through a it fills b 9 acting 

* Richards, Am. Jour, of Science (3), 8, 412; Trans. Am. Inst. 
Min. Engrs., 6, 492 (1874). 

f The pump will also work well using steam. 



8 



GAS AND FUEL ANALYSIS. 



as a continually falling piston drawing the current of 
air through e and its connections. These various 
forms of water-pumps should give a vacuum repre- 



V^ATER 



ROAM 




Fig. 5. — Richards' Jet-pump. Fig. 6. — Bunsen's Pump. 



sented by the height of the barometer less the tension 
of aqueous vapor at the temperature at which they 
are used, or about 29 inches of mercury. 



INTRODUCTION AND METHODS OF SAMPLING. 9 

II. STEAM-PUMPS. — Kochinke describes the appa- 
ratus in use in the Muldner Hiitten in Freiberg, 
shown at one-fifth size in Fig. 7. It consists of a 
glass tube drawn down to an opening 6 mm. in diam- 




t 
Fig. 7.— Steam Air-pump. 



eter; concentric with this, and held in place by the 
washer a> is the steam-jet 2 mm. in diameter, passing 
through the cork b, the cement c, and covering d. It 
is connected with the steam-pipe at g by webbed 
rubber tubing/; the air enters at e. This is said to 
give very good results and be economical in use of 
steam. 

In case neither water nor steam be available, 
recourse must be had to the ordinary rubber syringe- 
bulbs, provided with suitable valves, obtainable at any 
rubber store, or to a bottle aspirator. This consists of 
two one-gallon bottles, provided with doubly perfor- 
ated rubber stoppers, carrying tubes of glass or lead 
bent at right angles. In each bottle one of these tubes 
passes nearly to the bottom, and these are connected 
together by a piece of rubber tubing a yard long, 
carrying a screw pinchcock. The other tube in each 
case stops immediately under the stopper. Upon 
filling one of the bottles with water, inserting the 
stopper and blowing strongly through the short tube, 
water will fill the long tubes thus forming a siphon, 



10 GAS AND FUEL ANALYSIS. 

and upon lowering the empty bottle, a current of air 
will be sucked in through the short tube originally 
blown into ; this may be regulated by the screw 
pinchcock. 

In inserting the gas-sampling tube care should be 
taken not to insert it so close to the source of heat 
as to draw out the gases in a dissociated, i.e. partly 
decomposed, condition. 

In case of very smoky fuels it is well to filter the 
gases through rolls of fine wire gauze or asbestos ; 
in sucking them through a washing-bottle, the water 
may change the composition of the sample. 



CHAPTER II. 

APPARATUS FOR THE ANALYSIS OF CHIMNEY- 
GASES. 

In the writer's opinion the apparatus which is best 
adapted for this purpose is that of Orsat ; it is readily 
portable, not liable to be broken, easy to manipulate, 
sufficiently accurate, and — in the modification about to 
be described — always ready for use, there being no 
stopcocks to stick fast. 

As the Bunte and Elliott apparatus are also used 
for this purpose, they too will be described. 

Fischer's apparatus, using mercury, is rather too 
difficult for the average engineer ; Hempel's apparatus 
for the analysis of illuminating-gas might also be used ; 
it is, however, not customary. 

ORSAT APPARATUS. 

Description. — The apparatus Fig. 8, is enclosed in 
a case to permit of transportation from place to place; 
furthermore, the measuring-tube is jacketed with 
water to prevent changes of temperature affecting the 
gas-volume. The apparatus consists essentially of 
the levelling-bottle A, the burette B, the pipettes 
P f , P", P"\ and the connecting tube T. 

ii 



12 



GAS AND FUEL ANALYSIS. 



Manipulation. — The reagents in the pipettes should 
be adjusted in the capillary tubes to a point on the 
stem about midway between the top of the pipette 
and the rubber connector. This is effected by open- 
ing wide the pinchcock upon the connector, the 




Fig. 8.— Orsat's Gas Apparatus. 



bottle being on the table, and very gradually lower- 
ing the bottle until the reagent is brought to the point 
above indicated. Six inches of the tubing used corre- 
spond to but o.i cc, so that an error of half an inch 
in adjustment of the reagent is without influence 
upon the accuracy of the result. The reagents having 
been thus adjusted, the burette and connecting tube 
are completely filled with water by opening d and 
raising the levelling-bottle. The apparatus is now 



ANALYSIS OF CHIMNEY-GASES. 1 3 

ready to receive a sample of gas (or air for prac- 
tice). In case a flue-gas is to be analyzed d is con- 
nected with i, Fig. 2, A lowered and about 102 cc. 
of the gas forced over by opening h; or d may 
be connected with aT joint in the gas-stream; the 
burette after filling is allowed to drain one minute by 
the sand glass, c snapped upon its rubber tube, and 
the bottle A raised to the top of the apparatus. By 
gradually opening c the water is allowed to run into 
the burette until the lower meniscus stands upon the 
100 or o mark (according to the graduation of the 
apparatus). The gas taken is thus compressed into 
the space occupied by 100 cc, and by opening d the 
excess escapes. Open c and bring the level of the 
water in the bottle to the same level as the water in the 
burette and take the reading, which should be 100 cc. 
Special attention is called to this method of reading: 
if the bottle be raised, the gas is compressed; if 
lowered, it is expanded. 

Determination of Carbon Dioxide. — The gas to be 
analyzed is invariably passed first into pipette P', con- 
taining potassium hydrate for the absorption of carbon 
dioxide, by opening e and raising^. The gas dis- 
places the reagent in the front part of the pipette, 
laying bare the tubes contained in it, which being 
covered with the reagent present a large absorptive 
surface to the gas; the reagent moves into the rear 
arm of the pipette, displacing the air over it into the 
flexible rubber bag which prevents its diffusion into 
the air. The gas is forced in and out of the pipette 
by raising and lowering^, the reagent finally brought 
approximately to its initial point on the stem of the 



14 GAS AND FUEL ANALYSIS. 

pipette, the burette allowed to drain one minute, and 
the reading taken. The difference between this and 
the initial reading represents the cubic centimeters of 
carbon dioxide present in the gas. To be certain that 
all the carbon dioxide is removed, the gas should be 
passed a second time into P r and the reading taken 
as before; these readings should agree within o. I per 
cent. 

Determination of Oxygen. — The residue from the 
absorption of carbon dioxide is passed into the second 
pipette, P" , containing an alkaline solution of potas- 
sium pyrogallate, until no further absorption will take 
place. The difference between the reading obtained 
and that after the absorption of carbon dioxide, repre- 
sents the number of cubic centimeters of oxygen 
present. 

Determination of Carbonic Oxide. — The residue 
from the absorption of oxygen is passed into the third 
pipette, P"\ containing cuprous chloride, until no 
further absorption takes place; that is, in this case 
until readings agreeing exactly (not merely to o. i) are 
obtained. The difference between the reading thus 
obtained and that after the absorption of oxygen, 
represents the number of cubic centimeters of carbonic 
oxide present. 

Determination of Hydrocarbons The residue 

left after all absorptions have been made may consist, 
in addition to nitrogen, the principal constituent, of 
hydrocarbons and hydrogen. Their determination is 
difficult for the inexperienced, and, if desired, a sample 
of the flue-gas should be taken, leaving as little water 



ANALYSIS OF CHIMNEY-GASES. 1 5 

in the apparatus as possible, and sent to a competent 
chemist for analysis. 

Accuracy. — The apparatus gives results accurate to 
0.2 of one per cent. 

Time Required. — About twenty minutes are re- 
quired for an analysis; two may be made in twenty-five 
minutes, using two apparatus. 

Notes. — The method of adjusting the reagents is th& 
only one which has been found satisfactory: if the 
bottle be placed at a lower level and an attempt made 
to shut the pinchcock c upon the connector at the 
proper time, it will almost invariably result in failure. 

The process of obtaining ioo cc. of gas is exactly 
analagous to filling a measure heaping full of grain and 
striking off the excess with a straight-edge ; it saves 
arithmetical work, as cubic centimeters read off repre- 
sent percent directly. 

It often happens when e is opened, c being closed, 
that the reagent in P' drops, due not to a leak as is 
usually supposed, but to the weight of the column of 
the reagent expanding the gas. 

The object of the rubber bags is to prevent the 
access of air to the reagents, those in P" and P"' 
absorbing oxygen with great avidity, and hence if 
freely exposed to the air would soon become useless. 

Carbon dioxide is always the first gas to be removed 
from a gaseous mixture. In the case of air the per- 
centage present is so small, 0.08 to o. 1, as scarcely to 
be seen with this apparatus. It is important to use 
the reagents in the order given ; if by mistake the gas 
be passed into the second pipette, it will absorb not 
only oxygen, for which it is intended*, but also carbon 



l6 GAS AND FUEL ANALYSIS. 

dioxide; similarly if the gas be passed into the third 
pipette, it will absorb not only carbonic oxide, but 
also oxygen as well. 

The use of pinchcocks and rubber tubes, original 
with the author, although recommended by Naef,* is 
considered by Fischer, f to be inaccurate. The ex- 
perience of the author, however, does not support 
this assertion, as they have been found to be fully 
as accurate as glass stopcocks, and very much less 
troublesome and expensive. 

In case any potassium hydrate or pyrogallate be 
sucked over into the tube T or water in A, the analysis 
is not spoiled, but may be proceeded with by connect- 
ing on water at d, opening this cock, and allowing the 
water to wash the tubes out thoroughly. The addi- 
tion of a little hydrochloric acid to the water in the 
bottle A will neutralize the hydrate or pyrogallate, and 
the washing may be postponed until convenient. 

After each analysis the number of cubic centimeters 
of oxygen and carbonic oxide should be set down upon 
the ground-glass slip provided for the purpose. By 
adding these numbers and subtracting their sum from 
the absorption capacity (see Reagents) of each reagent, 
the condition of the apparatus is known at any time, 
and the reagent can be renewed in season to prevent 
incorrect analyses. 

BUNTE APPARATUS. 

Description. — The apparatus Fig. 9 consists of a 
burette — bulbed to avoid extreme length — provided 

* Wagner's Jahresb. 1885, p. 423. 

f Technologie d. Brennstoffe, foot note p. 295. 



ANALYSIS OF CHIMNEY-GASES. 



17 



at the top with a funnel /''and three-way cock 7, and 
a cock / at the bottom. These stopcocks are best 
of the Greiner and Friedrichs obliquely bored form. 
The burette is supported upon a retort- 
stand with a spring clamp. 

A " suction-bottle " S, an 8-oz. wide- 
mouthed bottle, fitted similarly to a 
wash-bottle, except that the delivery- 
tube is straight and is fitted with a 
four-inch piece of J-inch black rubber 
tubing, serves to withdraw the re- 
agents and water when necessary e A 
reservoir to contain water at the tem- 
perature of the room, fitted with along 
rubber tube, should be provided for 
washing out the reagents and filling 
the burette. 

Manipulation. — Before using the 
apparatus, the keys of the stopcocks 
should be taken out, wiped dry, to- 
gether with their seats, and sparingly 
smeared with vaseline or a mixture of 



n 



4 



vaseline and tallow and replaced. The Fig. 9.— Bunte's 
completeness of the lubrication can be Gas Apparatus - 
judged by the transparency of the joint, a thoroughly 
lubricated joint showing no ground glass. The 
burette is filled with water by attaching the rubber 
tube to the tip at / and opening the stopcocks at the 
top and bottom ; j is connected with the source whence 
the gas is to be taken, turned to communicate with 
the burette and opened, about 102 cc. of gas allowed 
to run in, andy and / closed. 



18 GAS AND FUEL ANALYSIS. 

The cup F \s filled with water to the 25-cc. mark, j 
turned to establish communication between it and the 
burette, the burette allowed to drain one minute by 
the sand-glass, and the reading taken, the cup being 
refilled to the mark if necessary. The readings are 
thus taken under the same pressure each time, i.e., 
this column of water plus the height of the barometer; 
and as the latter is practically constant during the 
analysis, no correction need be applied, it being within 
the limits of error. 

Determination of Carbon Dioxide. — The 'suc- 
tion-bottle " is connected with the tip of the burette, 
/ opened, and the water carefully sucked out nearly to 
/. The bottle is now disconnected, the burette dis- 
mounted from its clamp, using the cup as a handle, 
and the 25 cc. of water turned out. The tip is 
immersed under potassium hydrate contained in the 
No. 3 porcelain dish, and the cock / opened, then 
closed, and the tip wiped clean with a piece of cloth. 
The burette is now shaken, holding it by the tip and 
the cup, the thumbs resting upon j and /; more 
reagent is introduced, the absorption of the gas caus- 
ing a diminished pressure, and the operation repeated 
until no change takes place. The cup is now filled 
with water, j opened, and the reagent completely 
washed out into an ordinary tumbler placed beneath 
the burette. Four times filling of F should be suffi- 
cient for this purpose. The cup is now filled to the 
25-cc. mark, j opened, and the reading taken as 
before. 

The difference between this reading and the initial 
represents the number of cubic centimeters of carbon 



ANALYSIS OF CHIMNEY-GASES. 1 9 

dioxide; this divided by the volume of the gas taken 
gives the per cent of this constituent. 

Determination of Oxygen. — The water is again 
sucked out, and potassium pyrogallate solution intro- 
duced, similarly to potassium hydrate; this is dis- 
placed by water, and the reading taken as before. 
The difference between this and the last reading is the 
volume of oxygen present. 

Determination of Carbonic Oxide. — The water is 
removed for a third time, and acid cuprous chloride 
solution introduced and the absorption made as before ; 
this is washed out, first with water containing a little 
hydrochloric acid to dissolve the white cuprous chlo- 
ride which is precipitated by the addition of water, 
and finally with pure water, and the reading taken as 
before. The difference between this and the preced- 
ing gives the volume of carbonic oxide present. 

Notes. — Especial care should be taken not to grasp 
the burette by the bulb, as this warms the gas and 
renders the readings inaccurate. The stopcocks can 
conveniently be kept in the burette by elastic bands 
of suitable size. When the apparatus is put away for 
any considerable time, a piece of paper should be 
inserted between the key and socket of each stopcock 
to prevent the former from sticking fast. To ascer- 
tain when the absorption is complete, the burette is 
mounted in its clamp and allowed to drain until the 
meniscus is stationary, the dish containing the reagent 
raised until the tip is covered, /opened, and any change 
in level noted. If the meniscus rises, the absorption 
is incomplete and must be continued; if it remains 
stationary or falls, the absorption may be regarded as 



20 GAS AND FUEL ANALYSIS. 

finished. In case the grease from the stopcocks 
becomes troublesome inside the burette, it may be 
removed by dissolving it in chloroform and washing 
out with alcohol and then with water. The object in 
sucking the water not quite down to /, thus leaving a 
little water in the burette, is to discover if / leaks, the 
air rushing in causes bubbles. 

The object in washing out each reagent and taking 
all readings over water is to obviate corrections for 
the tension of aqueous vapor over potassium hydrate, 
hydrochloric acid, or any of the reagents which might 
be employed. The tension of aqueous vapor over 
seven per cent caustic soda is less than over water. 

Accuracy and Time Required. — The apparatus is 
rather difficult to manipulate, but fairly rapid — about 
twenty-five minutes being required for an analysis — 
and accurate to one tenth of one per cent. 

ELLIOTT APPARATUS. 

Description. — The apparatus Fig. 10 consists of a 
burette holding ioo cc. graduated in tenths of a cubic 
centimeter and bulbed like the Bunte apparatus — the 
bulb holding about 30 cc. ; it is connected with a 
levelling-bottle similar to the Orsat apparatus. The 
top of the burette ends in a capillary stopcock, the 
stem of which is ground square to admit of close con- 
nection with the " laboratory vessel,' ' an ungraduated 
tube similar to the burette, except of 125 cc. capacity. 
The top of this " vessel " is also closed with a capil- 
lary stopcock, carrying by a ground-glass joint a 
thistle-tube F y for the introduction of the reagents. 
The lower end of this " vessel M is closed by a rubber 



ANALYSIS OF CHIMNEY-GASES. 



21 



n 



75 



stopper carrying a three-way cock o, and connected 
with a levelling-bottle D. The 
burette and vessel are held upon a 
block of wood — supported by a ring 
stand — by fine copper wire tight- 
ened by violin keys. 

Manipulation. — The ground-glass 
joints are lubricated as in the Bunte 
apparatus. The levelling-bottles are 
filled with water, the stopcocks 
opened, and the bottles raised until 
the water flows through the stop- 
cocks m and n. m is connected 
with the source whence the gas to 
be analyzed is to be taken, n closed, 
D lowered and rather more than ioo 
cc. drawn in, and m closed, n is 
opened, D raised and E lowered, 
nearly ioo cc. of gas introduced, 
and n closed; by opening m and 
raising D the remainder of the gas 
is allowed to escape, the tubes being 
filled with water and m closed, n is 
opened and the water brought to 
the reference-mark; the burette is 
allowed to drain one minute, the 
level of the water in E is brought 
to the same level as in the burette, 
and the reading taken. 

Determination of Carbon Dioxide. — By raising E 9 
opening n, and lowering D, the gas is passed over into 
the laboratory vessel; F is filled within half an inch 



Fig. io. — Elliott 
Gas Apparatus. 



22 GAS AND FUEL ANALYSIS, 

of the top with potassium hydrate, o closed, m opened, 
and the reagent allowed to slowly trickle in. A No. 3 
evaporating-dish is placed under 0, and this turned to 
allow the liquid in the laboratory vessel to run into 
the dish. At first this is mainly water, and may be 
thrown away; later it becomes diluted reagent and 
may be returned to the thistle-tube. When the 
depth of the reagent in the thistle-tube has lowered 
to half an inch, it should be refilled either with fresh 
or the diluted reagent and allowed to run in until the 
absorption is judged to be complete, and the gas 
passed back into the burette for measurement. To 
this end close and then m, raise E, open n, and 
force some pure water into the laboratory vessel, thus 
rinsing out the capillary tube. Now raise D and lower 
E, shutting n when the liquid has arrived at the refer- 
ence-mark. The burette is allowed to drain a minute, 
the level of the water in the bottle E brought to the 
same level as the water in the burette, and the reading 
taken. 

Determination of Oxygen. — The manipulation is 
the same as in the preceding determination, potassium 
pyrogallate being substituted for potassium hydrate; 
the apparatus requiring no washing out. 

Determination of Carbonic Oxide. — The labora- 
tory vessel, thistle-tube, and bottle if necessary, are 
washed free from potassium pyrogallate and the 
absorption made with acid cuprous chloride similarly 
to the determination of carbon dioxide. The white 
precipitate of cuprous chloride may be dissolved by 
hydrochloric acid. 



ANALYSIS OF CHIMNEY-GASES. 23 

Accuracy and Time Required. — The apparatus is 
as accurate for absorptions as that of Orsat; it is 
stated to be much more rapid — a claim which the writer 
cannot substantiate. It is not as portable, is more 
fragile, and more troublesome to manipulate, and as 
the burette is not jacketed it is liable to be affected 
by changes of temperature. 

Notes. — In case at any time it is desired to stop 
the influx of reagent, o should be closed first and 
then m\ the reason being that the absorption may 
be so rapid as to suck air in through o, m being 
closed. 

The stopcock should be so adjusted as to cause the 
reagent to spread itself as completely as possible over 
the sides of the burette. 

By the addition of an explosion-tube it is used for 
the analysis of illuminating-gas,* bromine being used 
to absorb the li illuminants." Winkler f has shown 
that this absorption is incomplete, and Hempel $ that 
explosions of hydrocarbons made over water are in- 
accurate, so that the apparatus can be depended upon 
to give results upon methane and hydrogen only within 
about two per cent. 

GAS-BALANCES. 

Under this heading are included various devices 
either for weighing a volume of the chimney-gas, as 
the Econometer of Arndt,§ or weighing a globe in an 

* Mackintosh, Am. Chem. Jour., 9, 294. 

f Zeitsch. f. Anal. Chem., 28, 286. 

X Gasanalytische Methoden, p. 102. 

§ Zeit. d. Vereins dcutsch. Ingenieurc, 37, 801. 



H GAS AND FUEL ANALYSIS. 

atmosphere of the gas, as the Gas-balance of Custodis. 
The Gas-composimeter of Uehling* depends upon 
the laws governing the flow of gases through small 
apertures. 

They are difficult to adjust and keep in adjustment, 
requiring to be checked frequently by the Orsat appa- 
ratus, and are expensive. Their indications are within 
about half of one per cent of those given by the 
chemical apparatus. Only the presence of carbon di- 
oxide is indicated by them. 

* Poole, Calorific Power of Fuels, p. 150, 2d edition (1900). 



CHAPTER III. 
MEASUREMENT OF TEMPERATURE. 

In the majority of cases, the ordinary mercurial 
thermometer will serve to determine the temperature 
of the chimney-gases. It should not be inserted naked 
into the flue, but be protected by a bath of cylinder, 
or raw linseed oil, contained in a brass or iron tube. 
These tubes may be half an inch inside diameter and 
two to three feet in length. Temperatures as high as 
62 5 C. have been observed in chimneys; this lasts of 
course but for a moment, but would be sufficient to 
burst the unprotected thermometer. 

For the observation of higher temperatures, recourse 
must be had to the " high-temperature thermom- 
eters/ ' filled with carbon dioxide under a pressure of 
about one hundred pounds, giving readings to 550 C* 
These may be obtained of the dealers in chemical 
apparatus; some require no bath, being provided 
with a mercury-bath carefully contained in a steel 
tube, and the whole enclosed in a bronze tube.f 

* Those made by W. Apel, Gottingen, Germany, are about three 
feet long, the scale occupying about one foot, thus avoiding the 
necessity of withdrawing the thermometer from the bath for 
reading. H. J. Green of Brooklyn, N. Y., makes similar ones. 

f Hohmann Special Thermometers, made by Chas. J. Tagliabue, 
New York. 

25 



26 GAS AND FUEL ANALYSIS. 

These thermometers should be tested from time to 
time either by comparison with a standard or by inser- 
tion in various baths of a definite temperature. Some 
of the substances used for these baths are: water, boil- 
ing-point ioo° ; naphthalene, Bpt. 2 1 9 ; benzophenon, 
Bpt. 306 ; and sulphur,* Bpt. 445 . Care should be 
taken that the bulb of the thermometer does not dip 
into the melted substance, but only into the vapor, 
and that the stem exposure be as nearly as possible 
that in actual use. 

For the measurement of temperatures beyond the 
range of these thermometers the Le Chatelier thermo- 
electric pyrometer may be used. This consists of a 
couple formed by the junction of a platinum and 
platinum- 10$ rhodium wire, passing through fire-clay 
tubes in a porcelain or iron envelope and connected 
with a galvanometer. The hotter the junction is 
heated the greater the current and the galvanometer 
deflection; this latter is determined for several points, 
naphthalene, sulphur, and copper, Mpt. 1095 C, or 
even platinum, 1760 C, and a plot made with gal- 
vanometer-readings as abscissae and temperatures as 
ordinates. From this the temperature corresponding 
to any deflection is readily obtained. 

The exact description of the instrument and details 
of calibration are, however, beyond the scope of this 
work, and the student is referred for these to articles 
by Le Chatelier, Soci£t6 Technique de lTndustrie du 
Gaz, 1890, abstracted in Jour. Soc. Chem. Industry, 

* In testing the Hohmann thermometers in sulphur-vapor, the 
bronze tube should be prevented from corrosion by the vapor by 
a glass envelope. 



MEASUREMENT OF TEMPERATURE. 



27 



9, 326, and Holman, Proc. Am. Academy, 1895, p. 
234 ; later works are those of Le Chatelier and 
Boudouard, ;« High Temperature Measurements," 
transl. by G. K. Burgess (1901), and also C. L. 
Norton, l4 Notes on Heat Measurements " (1902). 

An error of 5 ° in the reading of the thermometer 
affects the final result by about 20 calories. 

In case neither of these methods be available nor 




Fig. 11. — Melting-point Boxes. 

applicable, use may be made of the melting-points 
of certain metals or salts contained in small cast-iron 
boxes, Fig. 11. The melting-points of certain metals 
and salts are given in Table VII. 



CHAPTER IV. 
CALCULATIONS. 

As has been already stated in the Introduction, the 
object of analyzing the flue-gases is to ascertain, first, 
the completeness of the combustion, especially the 
amount of air which has been used or the " pounds of 
air per pound of coal," and second, the amount of 
heat passing up chimney. 

I. To Ascertain the Number of Pounds of Air 
per Pound of Coal. — A furnace-gas gives 11.5$ CO a , 
7.4$ O, 0.9^ CO, and 80.2$ N. Data: atomic weights, 
O = 16, C = 12; weight liter C0 2 = 1.966 grs., of 
O, 1.43 grs., of CO, 1.25 1 grs. Find the number of 
grams of each constituent in 100 liters of the furnace- 
gas, and from this the weight of carbon and weight of 
oxygen. 1 1. 5 (liters C0 2 ) X 1.97 (wt. liter C0 2 ) = 

32/ O \ 
22.66 grms. CO a ; now — (pTT/ °^ ^ s ls oxygen = 

16.48 grms., 6.18 grms. is carbon. The weight of 
free oxygen is 7.4 X 1.43 = 10.58 grms. The weight 
of carbon and oxygen in the carbonic oxide is 0.9 X 

1.25= 1. 12 grms. CO. Now -(——] is oxygen or 0.64 

grm., and 0.48 grm. is carbon. There are then pres- 
ent in 100 liters of the gas 27.70 grms. oxygen and 
6.66 grms. carbon; corresponding to 120.0 grms. air 

28 



CA L CULA TIONS. 29 

to 6.66 grms. carbon, air being 23.1$ oxygen by 

grms. ) . grm. ) 

weight; or 18.02 * | air per ^ j carbon. If 

the coal be 83^ carbon, this figure must be diminished 
accordingly, giving in this case 14.95 lbs. air per lb. 
of coal. Theory requires 11.54 lbs. air per lb. of car- 
bon, but in practice the best results are obtained by 
increasing this from 50$ to 100$.* 

2. To Ascertain the Quantity of Heat Passing 
up Chimney — Determine the volume of gas generated 
from one kilo of coal when burned so as to produce 
the gas the analysis of which has just been made 
according to the directions given. The chemical 
analysis of the coal is as follows: moisture 1.5$, 
sulphur 1.2$, carbon 83$, hydrogen 2.5^, ash 11.4^, 
oxygen and nitrogen (by difference) 0.4$. Then 
there are in one kilo of coal 830 grms. carbon, of 
this suppose but 800 to be burned, the remaining 30 
grms. going into the ash; of the 800 grms. 618/666 
or 742 grms. produced carbon dioxide, and 48/666 
or 58 grms. produced carbonic oxide. From 6.18 
grms. carbon were produced 1 1.5 liters carbon di- 
oxide in the problem in I ; hence 742 grms. would 
furnish 1381 liters. 6. 18 : 742 : : 11. 5 \y. y = 1381. 
Similarly 58 grms. carbon would furnish 109.0 liters 
carbonic oxide. 0.48 : 58 :: 0.90 : z. ,2=109.0. The 
volume of oxygen can be found by the proportion 
1 1.5 (#CO a ): 7.4 (#0):: 1381 : x. x = 888 liters. In 
the same manner the nitrogen is found to be 9631 
liters. 1 1.5 : 80.2 : : 1381 : u. ^=9631. One kilo of 
coal under these conditions furnishes 1.38 1 cu. meters 

* Scheurer-Kestner, Jour, Soc. Chem, Industry, 7, 616. 



3° GAS AND FUEL ANALYSIS. 

carbon dioxide, o. 109 c. m. carbonic oxide, 0.888 
c. m. oxygen, and 9.631 c. m. nitrogen. 

The quantity of heat carried off by each gas is its 
rise of temperature X its weight X its specific heat, 
The specific heats of the various gases are shown in 
the table below, and for facility in calculation, a column 
is given obtained by multiplying the weight by the 
specific heat; multiplying the volumes obtained in the 
previous calculation by the numbers in this column 
and by the rise in temperature gives the number of 
calories (C) that each gas carries away. 

TABLE OF SPECIFIC HEATS OF VARIOUS GASES.* 

(n c u , Wt.ofCu. M. Sp.HeatX 

Name of Gas. Sp. Heat. T . „ T : , „ , _ Log. 

* Kg. Wt. of Cu. M. s 

Carbon dioxide (io°-35o°). 0.234 I# 97 0.463 9.6656 

44 monoxide 0.245 1.26 0.308 9.4886 

Oxygen 0.217 1.43 0.311 9.4928 

Nitrogen 0.244 1.26 0.306 9-4857 

Aqueous vapor 0.480 0.80 0.387 9-5877 

In the test the average temperature of the escaping 
gases was 275 C. ; that of the air entering the grate 
was 2 5 C, a rise of temperature of 250 C. As 
shown by the wet-and-dry-bulb thermometer, the air 
was 50 per cent saturated with moisture. 

The calculation of the heat carried away is then for: 

Cu. M. C. 

Carbon dioxide 1.381 X 250 X 0.463 = 160.0 

Carbonic oxide o. 109 X " X 0.308 = 8.4 

Oxygen 0.888 X " X 0.311 = 69.1 

Nitrogen 9.631 X " X 0.306 = 737.0 

Total 12.009 974-5 

* Fischer, Tech. d, Brennstoffe, p. 267. 



CA LCULA TIONS. 3 1 

There is, however, another gas passing up chimney 
of which we have taken no cognizance, namely, water- 
vapor; this comes from the moisture in the coal, from 
the combustion of hydrogen in the coal, and from the 
air entering the grate; its volume is calculated as 
follows: 

The moisture in the coal as found by chemical 
analysis was 1.5$ = 0.015 kg.; the hydrogen in the 
coal was 2.5$ = 0.025 kg. The amount of water this 
forms when burned is nine times its weight, 0.025 kg. 
X 9 = 0.225 kg. The moisture in the air entering the 
grate would be, if completely saturated, 22.9 grams 
per cubic meter, as shown by Table I ; it was, how- 
ever, but 50$ saturated. The quantity is then, the 
volume of air used per kilogram of coal X moisture 
contained in it, or 12.009 X 22.9 X 0.50 = 0.137 kg. 
The weight of aqueous vapor passing up chimney per 
kilogram of coal is 0.015 -f- 0.225 -f- 0. 137 = 0.377 
kg. ; the quantity of heat that this carries off is O.377 
X 250 X 0.480 = 45.2 C. The total quantity of heat 
passing up chimney is then 1019.7 C. The heat of 
combustion of this coal as found by Mahler's calori- 
metric bomb was 7220 C. ; hence the percentage of 
heat carried off is 1020/7220 = 14. i#. 

The preceding calculations though correct are 
tedious, so much so, as to almost preclude their use 
for an hourly observation of the firing. They should 
be employed, however, in making the final calculation 
of a boiler-test, using the averages obtained. 

In rapid work the following formula will be found 
more applicable : Let o and n represent the percent- 
ages of oxygen and nitrogen found in the chimney- 



32 GAS AND FUEL ANALYSIS. 

gas; then the ratio of the air actually used to that 
theoretically necessary is expressed by the formula 

21 

\ n. / 

Applying it in the case of the flue-gas given, it 
becomes 

21 21 



, 79 X 7- 4\ 137 

~sST 



-a 



= 1.533 ratio. 



Multiplying this by 11.54, the theoretical number of 
pounds of air per pound of carbon, we obtain 17.69 as 
against 18.02 on page 28. 

Bunte * has given a shorter method for the deter- 
mination of the quantity of heat passing up chimney, 
and one which does not involve the analysis of the 
coal. 

For every per cent of carbonic acid present 43.43 C. 
per cubic meter of flue-gases have been developed = W\ 
C= specific heat of the flue-gases per cubic meter; 
then W/C represents the initial temperature (which is 
never attained) the ratio of which to the actual exit 
temperature of the flue-gases shows the heat lost. If 
T= this initial temperature and / the rise of tempera- 
ture of the flue-gases, then t/T represents the heat 
lost in the chimney-gases. 

The following table gives the data for the calculation 
for both pure carbon and coal of average value. 

* Jour. f. Gasbeleuchtung, 43, 637 (1900) ; Abstr. Jour. Soc 
Chem. Industry, 19, 887. 



BUNTE'S CHART SHOWING HEAT LOST IN CI 

TEIV 




■ X. 
:y-gases from the carbonic acid and the 

TURE. 

FICIENCY 

ah to en on inn 

2500 

2400 



2300 



NT LOSS 



40 



30 



20 



10 



) 


60 


70 


80 


90 


100 






















































































































































































































































































































































































































































































































X 




















\\\ 




















;w\ 


\ 


















x\x 


w 


















\\^ 


x\\\ 


















NXN 


^ 


St 
















v \\\ 


\\vi 


















\\>\ 




k^x 


\ 














s^ 


8s 


\VC\ 


J\\\ 














^ 


^$ 


x^ 


m, 














•^x 


^^ 


<\X\X- 


X 












s>^ 


\\\ 


\NN> 


!nN>$§ 














^"\\ 




W\ N 






\ 










^V \ 






^SS^N> 


sjSSSSJ 


\\\\ 










^\\ 


^^ 


>^ 


^5 


^ 


f|k 










\\ 




^X 


^ 


S$$$$ 


M 


^\ 








^^^\^ 




^$\ 


^: 


^ 


« 


g^ 














^§5 


^$$ 


$S^ 


pp 


\ 






^~~^^. 




\J^: 






£$§§ 


^ 


ik • 






^z^- 








^$$ 


^ 


«? 


■n 














^^$ 


^$^$ 


§§§§§ 


§111111 


















^$§§^ 






















SIB 


ifiHhl 
















^5= 




^\ 



2200 



2100 



2000 



1900 



1800 



1700 



1600 



1500 



1400 £ 



1300 



UJ 

1200 H 



1100 3 

o 

1000 < 



900 ' 
800 
700 
600 
500 
400 
300 
200 
100 




To fact page 33. 



TABLE XL 




s 

o o o 

ACTUAL TEMPERATURE°C 



CALCULATIONS. 



33 



Per Cent of 

CO„ in 

Chimney Gas. 


Specific Heat 

of 
Chimney Gas. 


Initial Temperature, W/C, Degrees C. 


For Carbon 
= T. 


For Coal 
= T. 


Diff. for 

o.i^COj. 


I 

2 

3 
4 
5 
6 

7 
8 

9 

10 

ii 

12 

13 
14 
15 
16 


O.308 
O.310 
O.311 

O.312 

0.3I3 
O.314 

0.315 
O.316 
O.318 
O.319 
O.32O 
O.322 
O.323 
O.324 
O.324 
O.325 


141 

280 
419 

557 
694 

830 
962 
1096 
1229 
1360 
1490 
1620 
1750 
1880 
2005 
2130 


167 

331 

493 

652 

808 

961 

III2 

I26l 

I407 

1550 

I692 

183O 

I968 

2102 

2237 
2366 


16 
16 
16 
15 
15 
15 
15 
15 
14 
14 
14 
14 
13 
13 
13 



Applying this to the problem on page 29 we find 
the initial temperature T to be 1762 C, the rise of 
temperature of the gases was 250 C, the loss is 
250/1762 = 14.2$, against 14.1$ found by the calcu- 
lation page 31. 

Bunte also employs a partially graphical method for 
the determination of the loss of heat. In Table X 
the extreme left-hand column represents the tempera- 
tures which should be obtained by the combustion of 
the average coal with the formation of a chimney-gas 
containing the percentages of carbon dioxide in the 
column next it. Applying this to our case we find 
the theoretical temperature for 11.5$ C0 2 to be 1558 ; 
dividing the rise of temperature actually observed — 
250° — by this, we obtain 16.05$, or 2$ more than by 
the method of page 31. 



34 GAS AND FUEL ANALYSIS. 

Almost the identical result can be obtained from 
Table XI directly : if the point of intersection of the 
diagonal representing the per cent of carbon dioxide 
with the horizontal line denoting the actual tem- 
perature, on the right, be followed to the bottom of 
the table the per cent of loss is ascertained. 

Table XI is the lower right-hand corner of Table X 
enlarged. 

W. A. Noyes* states that the following formula 
gives close results and is also independent of the com- 
position of the coal. 

if. ioo-$CO a _ \ N 

Percentage loss = \o.on-{ Vrr\ 0.00605 J(t'—t). 

Lunge f has also given a shorter method for the cal- 
culation of the heat lost. 

Determination of Loss Due to Formation of Car- 
bonic Oxide. — On page 29 we see that 58 grams of 
carbon burned to carbonic oxide ; for every gram of 
carbon burned to carbonic oxide there is a loss of 
5.66 C, in this case a loss of 328 C. The heating 
value of the coal is 7220 C, hence the loss is 4.5 per 
cent. 

* Am. Chem. Journal, 19, 162. 

f Zeit. f. angewandte Chemie, 1889, 240. 



CHAPTER V. 

APPARATUS FOR THE ANALYSIS OF FUEL AND 
ILLUMINATING GASES. 

Hempel's Apparatus. 

Description. — The apparatus, Figs. 12 and 13, is 
very similar in principle to that of Orsat ; the burette 
is longer, admitting of the reading of small quantities 
of gas, and the pipettes are separate and mounted in 
brass clamps on iron stands. P shows a " simple' ' 
pipette* provided with a rubber bag; this form, after 
ten years of use, can be said to satisfactorily take the 
place of the cumbersome "compound " pipette. 

The pipette for fuming sulphuric acid f is shown at 
F y and differs from the ordinary in that vertical tubes 
after the manner of those in the Orsat pipettes replace 
the usual glass beads. This prevents the trapping of 
any gas by the filling, which was so common with the 
beads and glass wool. E represents the large explo- 
sion pipette, \ of about 250 cc. capacity, with walls half 
an inch thick ; the explosion wires enter at the top and 
bottom to prevent short-circuiting; mercury is the 
confining liquid. The small explosion pipette holds 

* Gill, Am. Chem. J., 14, 231 (1892). 
\ Id., J. Am. Chem. Soc, 18, 67 (1896). 
% Gill, J. Am. Chem. Soc, 17, 771 (1895). 

35 



36 



GAS AND FUEL ANALYSTS. 



about no cc. and is of glass, the same thickness as 
the simple pipettes. Water is here used as the confin- 
ing liquid, and also usually in the burette. 

An induction coil capable of giving a half-inch spark, 




Fig. 12. — Showing Hempel Burette connected with the 
Simple Pipette on the Stand. 



with a six-cell "Samson" battery, four "simple" 
pipettes and a mercury burette, complete the outfit. 

The burette should be carefully calibrated and the 
corrections may very well be etched upon it opposite 
the io-cc. divisions. 



APPARATUS. 



37 



In working with the apparatus the pipettes are placed 
upon the adjustable stand 5 and connection made with 
the doubly bent capillary tube. 

Manipulation. — To acquire facility with the use of 
the apparatus before proceeding to the analysis of 




Fig. 13. — Explosion Pipette for Mercury and Sulphuric 

Acid Pipette. 



illuminating-gas, it is well to make the following deter- 
minations, obtaining " check readings " in every case: 
I. Oxygen in air, by (1) absorption with phosphorus; 

(2) absorption with potassium (or sodium) pyrogallate; 

(3) by explosion with hydrogen. 



38 GAS AND FUEL ANALYSIS. 



I. DETERMINATION OF OXYGEN IN AIR. 

(i) By Phosphorus. — 100 cc. of air are measured 
out as with the Orsat apparatus, the burette being 
allowed to drain two minutes. The rubber connectors 
upon the burette and pipette are filled with water, the 
capillary tube inserted, as far as it will go, by a twist- 
ing motion, into the connector upon the burette, thus 
filling the capillary with water; the free end of the 
capillary is inserted into the pipette connector, the 
latter pinched so as to form a channel for the water 
contained in it to escape, and the capillary twisted and 
forced down to the pinch-cock. There should be as 
little free space as possible between the capillaries and 
the pinch-cock. Before using a pipette, its connector 
(and rubber bag) should be carefully examined for 
leaks, especially in the former, and if any found the 
faulty piece replaced. 

The pinch-cocks on the burette and pipette are now 
opened, the air forced over into the phosphorus, and 
the pinch-cock on the pipette closed ; action im- 
mediately ensues, shown by the white fumes; after 
allowing it to stand for fifteen minutes the residue is 
drawn back into the burette, the latter allowed to drain 
and the reading taken. The absorption goes on best 
at 20° C, not at all at below 15 C. ; it is very much 
retarded by small amounts of ethene and ammonia. 
No cognizance need be taken of the fog of oxides of 
phosphorus. 

(2) By Pyrogallate of Potassium. — 100 cc. of air 
are measured out as before, the carbon dioxide absorbed 
with potassium hydrate and the oxygen with potassium 



APPARA TUS. 39 

pyrogallate, as with the Orsat apparatus ; before setting 
aside the pyrogallate pipette, the number of cubic 
centimeters of oxygen absorbed should be noted upon 
the slate s on the stand. This must never be omitted 
with any pipette save possibly that for potassium 
hydrate, as failure to do this may result in the ruin of 
an important analysis. The reason for the omission in 
this case is found in the large absorption capacity — four 
to five litres of carbon dioxide — of the reagent. 

(3) By Explosion with Hydrogen. — 43 cc. of air 
and 57 cc. of hydrogen are measured out, passed into 
the small explosion pipette, the capillary of the pipette 
filled with water, the pinch-cocks and glass stop-cock 
all closed, a heavy glass or fine wire gauze screen 
placed between the pipette and the operator, the spark 
passed between the spark wires, and the contraction 
in volume noted. The screen should never be omitted, 
as serious accidents may occur thereby. The oxygen is 
represented by one third of the contraction. For very 
accurate work the sum of the combustible gases should 
be but one sixth that of the non-combustible gases, 
otherwise some nitrogen will burn and high results will 
be obtained; * that is, (H + O) : (N + H) :: 1 : 6. 

II. ANALYSIS OF ILLUMINATING-GAS. 

100 cc. of gas are measured from the bottle contain- 
ing the sample into the burette. 

Determination of Carbon Dioxide. — The burette 
is connected with the pipette containing potassium 

* This is shown in the work of Gill and Hunt, J. Am. Chem. 
Soc, 17, 987 (1895). 



40 GAS AND FUEL ANALYSIS. 

hydrate and the gas passed into it with shaking until 
no further diminution in volume takes place. 

Uluminants, C„H 2n , C W H W . 6 Series. — The rubber 
connectors are carefully dried out with filter-paper, a 
dry capillary used, and the gas passed into the pipette 
containing fuming sulphuric acid and allowed to stand, 
with occasional passes to and fro, for forty-five minutes. 
On account of the extremely corrosive nature of the 
absorbent it is not advisable to shake the pipette, as 
in case of breakage a serious accident might occur. 
For Boston gas this is sufficient, although with richer 
gases check readings to 0.2 cc. should be obtained. 
It is then passed into potassium hydrate, as in the 
previous determination, to remove any sulphurous acid 
which may have been formed and any sulphuric 
anhydride vapor, these having a higher vapor tension 
than water. The difference between this last reading 
and that after the absorption of the carbon dioxide 
represents the volume of " illuminants ' ' or " heavy 
hydrocarbons " present. 

Oxygen. — This is absorbed, as in the analysis of 
air, by potassium or sodium pyrogallate. 

Carbonic Oxide. — The gas is now passed into am- 
moniacal cuprous chloride, until the reading is constant 
to 0.2 cc. ; it is then passed into a second pipette, 
which is fresh, and absorption continued until constant 
readings are obtained. 

Methane and Hydrogen. — (a) Hinman s Method* 
— The gas left from the absorption of carbonic oxide 
is passed into the large explosion pipette. About half 
the requisite quantity of oxygen (40 cc.) necessary 

* Gill and Hunt, J. Am. Chem. Soc, 17, 9S7 (1895). 



APPARATUS. 41 

to burn the gas is now added, mercury introduced 
through the T in the connector sufficient to seal the 
capillary of the explosion pipette, all rubber connectors 
carefully wired, the pinch-cocks closed, and the pipette 
cautiously shaken. A screen of heavy glass or fine 
wire gauze is interposed between the operator and the 
apparatus, the explosion wires are connected with the 
induction coil, a spark passed between them and the 
pinch-cocks opened, sucking in the remainder of the 
oxygen. The capillary is again sealed with mercury, 
the stop-cock opened and closed, to bring the contents 
of the pipette to atmospheric pressure, and the explo- 
sion repeated as before, and the stop-cock opened. 

It may be found expedient, to increase the inflamma- 
bility of the mixture, to introduce 5 cc. of " detonating- 
gas, ' ' the hydrolytic mixture of hydrogen and oxygen. 
The gas in the pipette containing carbon dioxide, 
oxygen, and nitrogen is transferred to the mercury 
burette and accurately measured. The carbon dioxide 
resulting from the combustion of the marsh-gas is 
determined by absorption in potassium hydrate; to 
show the presence of an excess of oxygen, the amount 
remaining is determined by absorption with potassium 
pyrogallate. 

The calculation is given on page 43. For very 
accurate work a second analysis should be made, 
making successive explosions, using the percentages of 
methane and hydrogen just found as a basis upon which 
to calculate the quantity of oxygen to be added each 
time. The explosive mixture should be so proportioned 
that the ratio of combustible gas (i.e., CH 4 , H and O) 
is to the gases which do not burn (i.e., N and the 



42 GAS AND FUEL ANALYSIS. 

excess of CH 4 and H) as ioo is to about 50 (from 26 
to 64) ;* otherwise the heat developed is so great as 
to produce oxides of nitrogen, which, being absorbed 
in the potassium hydrate, would affect the determina- 
tion of both the methane and the hydrogen. The 
oxygen should preferably be pure, although commer- 
cial oxygen, the purity of which is known, can be 
used; the oxygen content of the latter should be tested 
from time to time, especially with different samples. 

(b) HempeV s Method^ — From 12 to 15 cc. of the 
gas are measured off into the burette (e.g., 13.2 cc.) 
and the residue is passed into the cuprous chloride 
pipette for safe keeping. That in the burette is now 
passed into the small explosion pipette; a volume of 
air more than sufficient to burn the gas, usually about 
85 cc, is accurately measured and also passed into the 
explosion pipette, and in so doing water from the 
burette is allowed to partially fill the capillary of the 
pipette and act as a seal. The rubber connectors upon 
the capillaries of the burette and pipette are carefully 
wired on, both pinch-cocks shut, and the stop-cock 
closed. The pipette is cautiously shaken, the screen 
interposed, the explosion wires connected with the 
induction coil, a spark passed between them, and the 
stfop-cock immediately opened. The gas in the pipette, 
containing carbon dioxide, oxygen, and nitrogen, is 
transferred to the burette, accurately measured, by 
reading immediately, to prevent the absorption of car- 
bon dioxide, and carbon dioxide and oxygen deter- 
mined in the usual way. 



* Bunsen, Gasometrische Methoden, 2d ed., p. 73 (1877). 
f Hempel, Gas Analytische Methoden, 3d ed., p. 245 (1901). 



APPARATUS. 



43 



Calculation. — {a) Hinman's Method. — 56.2 cc. of 
gas remained after the absorptions; 77.4 cc. of oxygen 
were introduced, giving a total volume of 133.6 cc. 

Residue after explosion 46.9 cc. 

Residue after CO a absorption 28.2 " 

Carbon dioxide formed t 18.7 " 

Contraction 133.6 — 46.9= 86.7 " 

Residue after O absorption 25.6 " 

Oxygen in excess, 28.2 — 25.6 = 2.6 " 

The explosion of marsh-gas or methane is repre- 
sented by the equation?" 



CH 



+ 



O. 



o. 



CO, 



+ 



H„0 



+ 



H o 



From this it is evident that the volume of carbon 
dioxide is equal to the volume of methane present; 
therefore in the above example, in the 56.2 cc. of gas 
burned there were 18.7 cc. methane. 

The total contraction is due (1) to the disappearance 
of oxygen in combining with the hydrogen of the 
methane, and (2) to the union of the free hydrogen 
with oxygen. The volume of the methane having 
been found, (1) can be ascertained from the equation 
above, equals twice the volume of the methane ; hence 

86.7 - (2 X 18.7) = 49-3 cc, 

contraction which is due to the combustion of hydrogen. 
This takes place according to the following reaction : * 



H, 


+ 


H, 


+ 


0, = 


H,0 


+ 


H 9 



* H a O being as steam at ioo° C. At ordinary temperatures 
this is condensed, giving rise to " total contraction." 



44 GAS AND FUEL ANALYSIS. 

Hydrogen then requires for its combustion half its 
volume of oxygen, hence this 49.3 cc. represents a 
volume of hydrogen with \ its volume of oxygen, or 
J- volumes; hence the volume of hydrogen is 32.9 cc. 

(b) HempeV s Method. — Of the 82 cc. of gas remain- 
ing after the absorptions, 13.2 cc. 'were used for the 
explosion ; 86.4 cc. air introduced giving a total volume 
of 99.6 cc. 

Residue after explosion 78.0 cc. 

Residue after C0 2 absorption 73 .2 



Carbon dioxide formed. 4.8 

Contraction 99-6 — 78.0 = 21 .6 

Residue after O absorption 70.2 

Oxygen in excess. .73.2 — 70.2 = 3.0 

The carbon dioxide being equal to the methane 
present, in the 13.2 cc. of gas burned, there were 
4.8 cc. of methane. The volume of methane is found 
by the proportion 13.2 : 82 :: 4.8 : 4, whence x = 
29.8 cc. 

The hydrogen is calculated similarly. 

The following method of calculation may be substi- 
tuted for that on page 43 : Let m = methane, h = 
hydrogen, c = total contraction, and O = oxygen 
actually used ; then 

2m + - = O 
1 2 



and 



3h 

2m + y = c > 



pp 


ARA TVS. 




3O - C 


111 


4 


h 


= c - O. 



45 

whence 



a:id 



The explosion can also be made after the absorption 
of oxygen and thus the troublesome absorption of car- 
bonic oxide avoided. The calculation is then, if C =: 
carbonic oxide, K = C0 2 formed: 

C 3h 

c = - + 2m + —, . . . . (1) 

K-C + m, (2) 

V = C + m + h; . . . . (3) 
whence 

h = V - K, 

c = 5 + v-^, 

3 T 3 

2K 2C 

3 ^ 3 

Another method for the estimation of hydrogen is 
by absorption with palladium sponge ; * it, however, 
must be carefully prepared, and it is the author's 
experience that one cannot be sure of its efficacy when 
it is desired to make use of it. A still better absorbent 
of hydrogen t is a I per cent solution of palladous 

* Hempel, Berichte deutsch. ch. Gesell., 12, 636 and 1006(1879). 
f Campbell and Hart, Am. Chem. J., 18, 294 (1896). 



46 GAS AND FUEL ANALYSIS. 

chloride at 50 C. ; when fresh this will absorb 20-50 
cc. of hydrogen in ninety minutes. A proportionately 
longer time is required if more hydrogen be present or 
the solution nearly saturated. The methane could 
then be determined by explosion or by mixing with 
air and passing to and fro over a white-hot platinum 
spiral in a tubulated pipette called the grisoumeter * 
(grisou = methane). 

Nitrogen. — There being no direct and convenient 
method for its estimation with this apparatus, the per- 
centage is obtained by finding the difference between 
the sum of all the percentages of the gases determined 
and 100 per cent. 

New f determines nitrogen in illuminating-gas di- 
rectly after the method of Dumas in organic sub- 
stances; 150 cc. of gas are used, the hydrocarbons 
partially absorbed by fuming sulphuric acid and the 
remainder burned in a combustion tube with copper 
oxide ; the carbon dioxide is absorbed and the residual 
nitrogen collected and measured. 

Accuracy and Time Required.— For the absorp- 
tions the apparatus is accurate to o. 1 cc. ; for explosions 
by Hinman's method J the methane can be determined 
within 0.2 per cent, the hydrogen within 0.3 per cent; 
by Hempel's method within 1 per cent for the methane 
and 7.5 per cent for the hydrogen. The time required 
for the analysis of illuminating-gas is from three to 
three and one-half hours; for air, from fifteen to twenty 
minutes. 

* Winkler, Frcs. Zeit., 28, 269 and 288. 
f J. Soc. Chem. Ind., II, 415 (1892). 
% Gill and Hunt, loc cit. 



APPARATUS. 47 

Notes. — The object in filling the capillaries of the 
explosion pipettes with water or mercury before the 
explosion is to prevent the bursting of the rubber con- 
nectors on them. With mercury this is effected by 
introducing it through the T joint in the connector. 
After testing for oxygen with the pyrogallate a small 
quantity of dilute acetic acid is sucked into the burette 
to neutralize any alkali which by any chance may have 
been sucked over into it. The acid is rinsed out with 
water and this forced out by mercury before the burette 
is used again. 

The water in the burette should be saturated with 
the gas which is to be analyzed — as illuminating-gas 
— before beginning an analysis. The reagents in the 
pipettes should also be saturated with the gases for 
which they are not the reagent. For example, the 
fuming sulphuric acid should be saturated with oxygen, 
carbon monoxide, methane, hydrogen, and nitrogen; 
this is effected by making a blank analysis using 
illuminating-gas . 

The method of analysis of the residue after the 
absorptions have been made by explosion is open to 
two objections: 1st, the danger of burning nitrogen by 
the violence of the explosion; and 2d, the danger of 
breakage of the apparatus and possible injury to the 
operator. These may be obviated by employing the 
apparatus of Dennis and Hopkins,* which is practically 
a grisoumeter with mercury as the confining liquid ; or 
that of Jager, t who burns the gases with oxygen in a 

* J. Am. Chem. Soc, 21, 398 (1899). 

f J. f. Gasbeleuchtung, 41, 764. Abstr. J. Soc. Chem. Ind., 
17, 1190 (1898). 



48 GAS AND FUEL ANALYSIS. 

hard-glass tube filled with copper oxide. By heating 
to 250 C. nothing but hydrogen is burned; higher 
heating of the residue burns the methane. 

To the method of explosion by the mixture of an 
aliquot part of the residue with air, method (b) y there 
is the objection that the carbon dioxide formed is meas- 
ured over water in a moist burette, giving abundant 
opportunities for its absorption, and that the errors in 
analysis are multiplied by about six, in the example 

£20- 
13^' 



by * 



CHAPTER VI. 

REAGENTS AND ARRANGEMENT OF THE 
LABORATORY. 

The reagents used in gas-analysis are comparatively 
few and easily prepared. 

Hydrochloric Acid, Sp. gr. i.io. — Dilute "muri- 
atic, acid " with an equal volume of water. In addi- 
tion to its use for preparing cuprous chloride, it finds 
employment in neutralizing the caustic solutions which 
are unavoidably more or less spilled during their use. 

Fuming Sulphuric Acid. — Saturate " Nordhausen 
oil of vitriol " with sulphuric anhydride. Ordinary 
sulphuric acid may be used instead of the Nordhausen ; 
in this case about an equal weight of sulphuric an- 
hydride will be necessary. Absorption capacity \ I cc. 
absorbs 8 cc. of ethene (ethylene). 

Acid Cuprous Chloride. — The directions given in 
the various text-books being troublesome to execute, 
the following method, which is simpler, has been 
found to give equally good results. Cover the bottom 
of a two-liter bottle with a layer of copper oxide or 
" scale f in. deep, place in the bottle a number of 
pieces of rather stout copper wire reaching from top 
to bottom, sufficient to make a bundle an inch in 
diameter, and fill the bottle with common hydrochloric 

49 



50 GAS AND FUEL ANALYSIS. 

acid of 1. 10 sp. gr. The bottle is occasionally shaken, 
and when the solution is colorless, or nearly so, it is 
poured into the half-liter reagent bottles, containing 
copper wire, ready for use. The space left in the 
stock bottle should be immediately filled with hydro- 
chloric acid (i.io sp. gr.). 

By thus adding acid or copper wire and copper 
oxide when either is exhausted, a constant supply of 
this reagent may be kept on hand. 

The absorption capacity of the reagent per cc. is, 
according to Winkler, 15 cc. CO; according to 
Hempel 4 cc. The author's experience with Orsat's 
apparatus gave 1 cc. 

Care should be taken that the copper wire does not 
become entirely dissolved and that it extend from the 
top to the bottom of the bottle; furthermore the 
stopper should be kept thoroughly greased the more 
effectually to keep out the air, which turns the solution 
brown and weakens it. 

Ammoniacal Cuprous Chloride. — The acid cu- 
prous chloride is treated with ammonia until a faint 
odor of ammonia is perceptible; copper wire should 
be kept in it similarly to the acid solution. This 
alkaline solution has the advantage that it can be 
used when traces of hydrochloric acid vapors might 
be harmful to the subsequent determinations, as, for 
example, in the determination of hydrogen by absorp- 
tion with palladium. It has the further advantage 
of not soiling mercury as does the acid reagent. 

Absorption capacity, 1 cc. absorbs 1 cc. CO. 

Cuprous chloride is at best a poor reagent for the 
absorption of carbonic oxide; to obtain the greatest 



REAGENTS AND LABORATORY. 5 I 

accuracy where the reagent has been much used, the 
gas should be passed into a fresh pipette for final 
absorption, and the operation continued until two 
consecutive readings agree exactly. The compound 
formed by the absorption — possibly Cu 2 COCl 2 — is very 
unstable, as carbonic oxide may be freed from the 
solution by boiling or placing it in vacuo ; even if it 
be shaken up with air, the gas is given off, as shown 
by the increase in volume and subsequent diminution 
when shaken with fresh cuprous chloride. 

Hydrogen. — A simple and effective hydrogen gen- 
erator can be made by joining two six-inch calcium 
chloride jars by their tubulatures. Pure zinc is filled 
in as far as the constriction in one, and the mouth 
closed with a rubber stopper carrying a capillary tube 
and a pinch-cock. The other jar is filled with 
sulphuric acid I : 5 which has been boiled and cooled 
out of access of air. The mouth of this jar is closed 
with a rubber stopper carrying one of the rubber bags 
used on the simple pipettes. 

Mercury. — The mercury used in gas analysis should 
be of sufficient purity as not to " drag a tail" when 
poured out from a clean vessel. It may perhaps be 
most conveniently cleaned by the method of J. M. 
Crafts, which consists in drawing a moderate stream 
of air through the mercury contained in a tube about 
3 feet long and i\ inches internal diameter. The tube 
is supported in a mercury-tight V-shaped trough, of 
size sufficient to contain the metal if the tube breaks, 
one end being about 3 inches higher than the other. 
Forty-eight hours' passage of air is sufficient to purify 
any ordinary amalgam. The mercury may very well 



52 GAS AND FUEL ANALYSIS. 

be kept in a large separatory funnel under a layer of 
strong sulphuric acid. 

Palladous Chloride. — 5 grams palladium wire are dis- 
solved in a mixture of 30 cc. hydrochloric and 2 cc. nitric 
acid, this evaporated just to dryness on a water-bath, re- 
dissolved in 5 cc. hydrochloric acid and 2 5 cc. water, and 
warmed until solution is complete. It is diluted to 750 cc. 
and contains about one per cent of palladous chloride. It 
will absorb about two thirds of its volume of hydrogen. 

Phosphorus. — Use the ordinary white phosphorus 
cast in sticks of a size suitable to pass through the 
opening of the tubulated pipette. 

Potassium Hydrate. — (a) For carbon dioxide de- 
termination, 500 grams of the commercial hydrate is 
dissolved in 1 liter v{ water. 

Absorption capacity, 1 cc. absorbs 40 cc, C0 2 . 

(b) For the preparation of potassium pyrogallate 
for special work, 120 grams of the commercial hydrate 
is dissolved in 100 cc. of water. 

Potassium Pyrogallate. — Except for use with the 
Orsat or Hempel apparatus, this solution should be 
prepared only when wanted. The most convenient 
method is to weigh out 5 grams of the solid acid upon 
a paper, pour it into a funnel inserted in the reagent 
bottle, and pour upon it 100 cc. of potassium hydrate 
(a) or (b). The acid dissolves at once, and the solution 
is ready for use. 

If the percentage of oxygen in the mixture does 
not exceed 28, solution (a) may be used;* if this 
amount be exceeded, (/;) must be employed. Other- 
wise carbonic oxide may be given off even to the 
extent of 6 per cent. 

* Clowes, Jour. Soc. Chem. Industry, 15, 170. 



REAGENTS AND LABORATORY. S3 

Attention is called to the fact that the use of potas- 
sium hydrate purified by alcohol has given rke to 
erroneous results. 

Absorption capacity ', I cc. absorbs 2 cc. O. 

Sodium Hydrate. — Dissolve the commercial hy- 
drate in three times its weight of water. This may be 
employed in all cases where solution (a) of potassium 
hydrate is used. The chief advantage in its use is its 
cheapness, it costing but one tenth as much as potas- 
sium hydrate, a point to be considered where large 
classes are instructed. Sodium pyrogallate is, how- 
ever, a trifle slower in action than the corresponding 
potassium salt. 

ARRANGEMENT OF THE LABORATORY. 

The room selected for a laboratory for gas-analysis 
should be well lighted, preferably from the north and 
east. To prevent changes in temperature it should 
be provided with double windows, and the method of 
heating should be that which will give as equable a 
temperature as possible. In the author's laboratory, 
instead of the usual tables, shelves are used, 18 inches 
wide and ij inches thick, best of slate or soapstone, 
firmly fastened to the walls, 30 inches from the floor; 
the Orsat apparatus, when not in use, may be sus- 
pended from these. The reagents are contained in 
half-liter bottles fitted with rubber stoppers, placed 
upon a central table convenient to all. Here are 
found scales, funnels and graduates for use in making 
up reagents. Distilled water is piped around to each 
place by -J-inch tin pipe and T 3 g-inch rubber tubing 
from a J-inch "main," being supplied at the tern- 



54 



GAS AND FUEL ANALYSIS. 



perature of the room from bottles placed about six 
feet above the laboratory shelves. A supply of a 
gallon per day per student should be provided. 

At the right of each place is fixed a sand-glass of 
cylindrical rather than conical form, graduated to 
minutes for the draining of the burettes. The "egg- 
timers " found in kitchen-furnishing stores serve the 
purpose admirably. 

li Unknown gases " for analysis are best contained 
in a Muencke double aspirator, Fig. 14, where they 




Fig. 14. — Muencke's Aspirator. 

can be thoroughly mixed before distribution and con- 
veyed by a pipe to the central table. 

Finally, the laboratory should contain a stone-ware 
sink provided with an efficient trap of the same 



REAGENTS AND LABORATORY. 55 

material, to prevent mercury from being carried into 
and corroding the lead waste-pipes. 

Drawers should be provided with compartments for 
various sizes of rubber connectors, pinchcocks, glass 
tubing, stoppers and fittings, and tools. When work- 
ing with the Orsat apparatus alone, three feet of shelf 
space may be allowed to each student; when using this 
with another, as, for example, the Bunte, another 
foot should be added. 

The course which the writer has been in the habit 
of giving to the Mechanical and Electrical Engineers 
embraces two exercises in the laboratory of two hours 
each, supplemented with four hours of lectures. The 
students in the laboratory make an analysis of air and 
an "unknown' furnace-gas, take and analyze an 
actual sample of chimney-gas, and make the calculation 
of heat lost and air used. In the lectures, the subject 
of gas-analysis and its other applications, and of fuels, 
their origin, description, preparation, analysis, and 
determination of heating value, are described. 



CHAPTER VII. 

FUELS— SOLID, LIQUID, AND GASEOUS: THEIR 
DERIVATION AND COMPOSITION. 

The substances employed as fuels are: 

a. Solid Fuels. — Wood, peat, brown, bituminous 
and anthracite coal, charcoal, coke, and oftentimes 
various waste products, as sawdust, bagasse, straw, 
and spent tan. 

b. Liquid Fuels. — Crude petroleum and various 
tarry residues. 

c. GASEOUS FUELS. — Natural gas, producer, blast- 
furnace, water, and illuminating gas. 

The essential constituents in all these are carbon and 
hydrogen; the accessory, oxygen, nitrogen, and ash; 
and the deleterious, water, sulphur, and phosphorus. 

a. Solid Fuels. 

Wood is composed of three substances — cellulose, 
or woody fibre (C 6 H 10 O B ) M ; the components of the sap, 
the chief of which is lignine, a resinous substance of 
identical formula with cellulose; and water. The 
formation of cellulose from carbon dioxide and water 
may be represented by the equation 

6CO,+ 5 H,O = C 6 H 10 O 6 + 6O a . 

The amount of water which wood contains determines 
its value as a fuel. This varies from 29 per cent in ash 

56 



FUELS— SOLID, LIQUID, AND GASEOUS. 57 

to 50 per cent in poplar; it varies also with the season 
at which the wood is cut, being least when the sap is in 
the roots — in December and January. This difference 
may amount to 10 per cent in the same kind of wood. 

The harder varieties of wood make the best fuel, a 
cord of seasoned hardwood being about equal to a ton 
of coal. Yellow pine, however, has but half this 
value; the usual allowance in a boiler-test is 0.4 the 
value of an equal weight of coal. 

The ash of wood is mainly potassium carbonate, 
with traces of other commonly occurring substances, 
as lime, magnesia, iron, silica, and phosphoric acid. 

The percentage composition of wood may be con- 
sidered as approximately, 



Waters 


Carbon. 


Hydrogen. 


Oxygen. 


Ash. 


Sp. Gr. 


20 


39 


4.4 


35-6 


I 


0.5.* 



When burned it yields about 4000 C. per kilo, and 
requires 6 times its weight of air or 4.6 cu. m. (74.1 
cu. ft. per pound) for its combustion. 

Peat finds considerable application in Europe, and 
is coming into use in this country in the form of bri- 
quettes. To this end it is reduced to a dry powder 
and compressed into small cylindrical blocks ; it is 
claimed to be as efficient as coal at half the price. It 
is also proposed to gasify peat after the manner of 
coal. Peat is produced by the slow decay underwater 
of certain swamp plants, more especially the mosses 
(Sphagnaceae), evolving methane (CH 4 ) (marsh-gas) 
and carbon dioxide (CO a ). 

It contains considerable moisture, from 20 to 50 
per cent, and 10 per cent even when "thoroughly 

* Mills & Rowan, Fuels, p. II. 



5§ GAS AND FUEL ANALYSIS. 

dry." Thirty per cent of its available heat is employed 
in evaporating this moisture. The high content of 
ash, from 3 to 30 per cent, averaging 15 per cent, also 
diminishes its value as a fuel. 

The ash of peat differs from that of wood in contain- 
ing little or no potassium carbonate. 

The percentage composition of peat may be consid- 
ered as approximately, 

Water. Carbon. Hydrogen. Oxygen. Nitrogen. Ash. Sp. Gr. 
German . 16.4 41.0 4.3 23.8 2.6 11.9 1.05 

American... 20.8 40.8 4.4 26.6 7.7 — 

Such peat is about equivalent to wood in its heating 
effect, one pound evaporating from 4.5 to 5 pounds 
of water. 

Coal. — Geologists tell us that coal was probably 
produced by the decay under fresh water of plants 
belonging principally to the Conifer, Fern and Palm 
families; these flourished during the Carboniferous 
Age to an extent which they never approached before 
or since. Representatives of the last family, which 
it is thought produced most of the coal, have been 
found 2 to 4 feet in diameter and 80 feet in height. 

By their decay, carbon dioxide " choke-damp/' 
marsh-gas " fire-damp/ ' and water were evolved. 
The change might be represented by the equation 

6C„H 10 O, = ;C0 2 + 3 CH 4 + i 4 H,0 + C 26 H, O 9 . 

Cellulose. Bituminous Coal. 

Some idea of the density of the vegetation and the 
time required may be obtained from the fact that it 
has been calculated that 100 tons of vegetable matter 
— the amount produced per acre per century — if com- 
pressed to the specific gravity of coal and spread over 



FUELS— SOLID, LIQUID, AND GASEOUS. 59 

an acre would give a layer less than 0.6 of an inch 
thick. Now four fifths of this is lost in the evolution 
of the gaseous products, giving as a result an accumu- 
lation of one eighth of an inch per century, or one foot 
in 10,000 years.* 

Brown Coal or Lignite may be regarded as forming 
the link between wood and coal ; geologically speaking 
it is of later date than the true coal. Most of the coal 
west of the Rocky Mountains is of this variety. 

As its name denotes, it generally is of brown color 
— although the western coal is black — and has a con- 
choidal fracture. It contains a large quantity of 
water when first mined, as much as 60 per cent, and 
when " air-dry " from 15 to 20 per cent. The per 
cent of ash is also high, from 1 to 20 per cent. 

The average moisture and ash in American lignites 
are 12.75 and 6.1 respectively. 

The percentage composition of brown coal may be 
considered as approximately, 

Water. Carbon. Hydrogen. Oxygen & Nitrogen. Ash. Sp. Gr. 

German 18.0 50.9 4.6 16.3 10.2 1.3 

Bituminous Coal. — This is the variety from which all 
the following coals are supposed to have been formed, 
by a process of natural distillation combined with pres- 
sure. According to the completeness of this process 
we have specimens which contain widely differing quan- 
tities of volatile matter. This forms the true basis for 
the distinguishing of the varieties of coal. In ordinary 
bituminous coal this volatile matter amounts to 30 or 
40 per cent. Three varieties of bituminous coal are 
ordinarily distinguished, as follows: 



* In case the student desires to follow in a more extended 
Hanger the geology of coal, reference may be had to Le Conte's 
Elements of Geologv," pp. 345-414 ^d ed. 



60 GAS AND FUEL ANALYSIS. 

Dry or non-caking —those which burn freely with but 
little smoke and — as the name denotes — do not cake 
together when burned. The coals from Wyoming 
are an example of this class. 

Caking — those which produce some smoke and cake 
or sinter together in the furnace. An example of 
these is the New River and Connellsville coal. 

Fat or Long-flaming — those producing much flame 
and smoke and do or do not cake in burning; volatile 
matter 50 per cent or more. Some of the Nova 
Scotia coals belong to this class. 

Bituminous coal varies much in its composition — is 
black or brownish black, soft, friable, lustrous, and of 
specific gravity of 1.25 to 1.5. 

Moisture varies from 0.25 to 8 per cent, averaging 
about 5. 

The percentage composition of bituminous coal may 
be considered as approximately,* 



Water. 


Carbon. Hydrogen. 


Oxygen. Nitrogen. 
0.7 1.6 


Ash. 


Sulphur. 


0.9 


77.1 5.2 


7.6 


I.O 


Water. 


Volatile Matter. 


Fixed Carbon. 




Ash. 


0.9 


27.4 


64.I 




7.6 



Semi-Bituminous or Semi-Anthracite Coal is upon the 
border-line between the preceding and the following 
variety; it is harder or softer than bituminous, contains 
less volatile matter (15 to 20 per cent), and burns 
with a shorter flame. An example of this is the 
Pocahontas coal. 

The percentage composition of semi-bituminous and 
semi- anthracite coal may be considered to be approxi- 
mately,* 

Water. Carbon. Hydrogen. Oxygen. Nitrogen. Ash. Sulphur. 

0.5 83.O 4.7 4.2 1.3 5.5 0.8 

Water. Volatile Matter. Fixed Carbon. Ash. 

o.5 i^7 77^3 iv5__ 

* II. J. Williams. 



FUELS— SOLID, LIQUID, AND GASEOUS, 6 1 

Anthracite Coal is the hardest, most lustrous, and 
densest of all the varieties of coal, having a specific 
gravity of 1.3 to 1.75; it contains the most carbon 
and least hydrogen and volatile matter (5 to 10 per 
cent). It has a vitreous fracture and kindles with 
difficulty, burning with a feeble flame, giving little or 
no smoke and, w r ith sufficient draft, an intense fire. 
The Lehigh coal is an excellent example of this class. 

The percentage composition of anthracite coal may 
be considered as approximately,* 

Water. Carbon. Hydrogen. Oxygen. Nitrogen. Ash. Sulphur. 

2.0 83.9 2.7 2.8 0.8 7.2 0.6 

Water. Volatile Matter. Fixed Carbon. Ash. 

2.0 4.3 86.5 7.2 

The ash of coal varies from 1 to 20 per cent 
and is mainly clay — silicate of alumina — with lime, 
magnesia, and iron. When coal is burned it yields 
from 6100 to 8000 C. and requires about 12 times its 
weight of air, 9.76 cu. m. per kilo or 156.7 feet per 
pound. For the greatest economy Scheurer-Kestner f 
found that this should be increased from 50 to 100 
per cent. 

Charcoal is prepared by the distillation or smoulder- 
ing of wood, either in retorts, where the valuable 
by-products are saved, or in heaps. It should be 
jet-black, of bright lustre and conchoidal fracture. 

When wood is charred in heaps only about 20 per 
cent of its weight in charcoal is obtained — 48 bushela 
per cord, or about half the percentage of carbon. 
When retorts or kilns are employed, the yield is in- 
creased to 30 per cent, and 40 per cent of pyroligneous 

*H. J. Williams. 

f Jour. Soc. Chem. Industry, 7, 616. 



62 GAS AND FUEL ANALYSIS. 

acid of 10 per cent strength, with 4 per cent of tar, 
are obtained. 

The percentage composition of wood-charcoal may be 
considered as approximately, 

Carbon. Ash. Sp. Gr. 

97.0 3.0 0.2 

Coke is prepared by the distillation of bituminous 
coal in ovens; these are of two types, those in which 
the distillation-products are allowed to escape — the 
" beehive " ovens — and those in which they are care- 
fully saved, as the Otto-Hoffman, Semet-Solvay, 
Simon-Carves', and others. 

The " beehive" ovens yield from 50 to 65 per 
cent of the weight of the coal — about 2\ tons. The 
Otto-Hoffman ovens are long narrow thin-walled re- 
torts 33 by 6 by 1 . 5 feet,* regeneratively heated by side 
and bottom flues; the charge is about 6 tons of coal, 
and the following percentage yields of by-products 
are obtained: coke 70-75, gas 16 (10 M. cu. ft.), tar 
3.3-5.6, ammonia o. 3—1.4."}- The Semet-Solvay ovens 
differ from the above in that they are not regen- 
eratively heated and their walls are thicker, serving to 
store up the heat ; the yield of coke is somewhat 
higher — about 80 per cent.;}: The by-products ob- 
tained alone increase the value of the output about 
one and one half times. Good coke should possess a 
cellular structure, a metallic ring, contain practically 
no impurities, and be capable of bearing a heavy 
burden in the furnace. 

* Irwin, Eng. Mag., Oct. 1901, abstr. J. Am. Chem. Soc, 24, 40. 
\ H. O. Hofman, Tech. Quar., IX, 212 (1898). 
% Pennock, J. Am. Chem. Soc, 21, 678 (1899). 



FUELS— SOLID, LIQUID, AND GASEOUS. 63 

The analysis of Connellsville coke with the coal 
from which it is prepared is given below. 

Water. Volatile Matter. Carbon. Sulphur. Ash. 

Coal I.26 30.I 59.62 O.78 8.23 

Coke 0.03 1.29 89.15 0.084 9»52 

Otto-Hoffman coke: 

Fixed Carbon. 
3.7 1.3 86.1 8.9 

Heating value 7100 C. 

The Minor Solid Fuels. 

Sawdust and Spent Tan-bark find occasional use, 
their value depending upon the quantity of moisture 
they contain. With 57 per cent of moisture 1 pound 
of tan-bark gave an evaporation of 4 pounds of water. 

Wheat Straw finds application as fuel in agricul- 
tural districts, 3^ pounds being equal to 1 ppund of 
coal. Upon sugar-plantations the crushed cane or 
Bagasse, partially dried, is extensively used as a 
fuel. With 16 per cent of moisture an evaporation 
of 2 pounds of water per pound of fuel has been 
obtained. 

b. Liquid Fuels. 

These consist of petroleum and its products, and 
various tarry residues from processes of distillation, 
as from petroleum, coking-ovens, wood and shale. 
Liquid fuel possesses the advantage that it contains no 
ash, is easily manipulated, the fire is of very equable 
temperature, very hot, and practically free from smoke. 

Regarding the origin of petroleum, many theories 
have been proposed. That of Engler,* that it was 
formed by the distillation under pressure of animal fats 

* Jour. Soc. Chem. Industry, 14, 648. 



64 GAS AND FUEL ANALYSIS. 

and oils, the nitrogenous portions of the animals pre- 
viously escaping as amines, seems most probable; it 
has yielded the best results of any hypothesis when 
tested upon an industrial scale. 

Crude Petroleum varies greatly in color according 
to the locality; it is usually yellowish, greenish, or 
reddish brown, of benzine-like odor, and sp. gr. of 0.78 
to 0.80. It " flashes " at the ordinary temperature; 
hence great care should be employed in its use and 
storage. Its percentage composition is shown below. 

Carbon. Hydrogen. 

84.0-85.O 16. 0-15.O 

It is more than twice as efficient as the best anthra- 
cite coal. In practice 14 to 16 pounds of water per 
pound of petroleum have been evaporated, and an 
efficiency of 19,000 B. T. U. was obtained as against 
8500 B. T. U. for anthracite. In general 3i to 4 bar- 
rels of oil are equivalent to a ton of good soft coal.* 

c. Gaseous Fuels. 

Natural Gas is usually obtained when boring for 
petroleum and consists mainly of methane and hydro- 
gen, although the percentage varies with the locality. 
The Findlay, Ohio,f gas is of the following composi- 
tion: 

CH 4 H N O C 2 H 4 CO a CO H a S Sp Gr. 

92.6 2.3 3.5 0.3 0.3 0.3 0.5 0.2 0.57 

* W. B. Phillips, Texas Petroleum (1900), p. 84. 
\ Orton, Geology of Ohio, vol VI. p. 137. 



FUELS—SOLID, LIQUID, AND GASEOUS. 65 

Blast-furnace, Producer, or Generator Gas is the 

waste gas issuing from the top of a blast-furnace or ob- 
tained by partially burning coal by a current of air (pro- 
duced by steam) in a special furnace — a gas-producer or 
generator. It is mainly carbonic oxide and nitrogen. 





CO 


N 


co 2 


H 


CH 4 


O 


B.T.U. per 
Foot. 


Blast-furnace gas 


34 3 


63.7 


0.6 


1.4 


— 


— 


— 


Gas from bitumin. coal 


24.5 


46.8 


3-7 


17.8 


6.8 


0.4 


223 


tt a tt '1 


25.0 


41.4 


4.0 


19.4 


9 .6 


0.6 


— 


" " anthrac. " 


27.0 


57-3 


2.5 


12.0 


1.2 


— 


— 


t< a a tt 


17.2 


53-1 


8.6 


18.2 


2.4 


0.4 


140 


a tt a a 


26.0 


47-° 


8.0 


18.5 


o.5 


— 


145* 



One ton of coal yields from i6of to 170 thousand 
cubic feet of gas of 156 to 138 B.T.U. heating power, or 
81 to 86 or even 90 per cent of the value of the coal. 

Water-gas. — If, instead of passing simply air over 
hot coal, water-vapor, or rather steam, be employed, 
it is decomposed, giving carbonic oxide and hydrogen, 
according to the equation H 2 -{- C = CO -f- H a , and 
the resulting mixture is called water-gas. The per- 
centage composition, which varies according to the ap- 
paratus and fuel employed, is about as follows: 





CO 


H 


CH 4 


co 2 


N 


O 


lilts. 


Sp. Gr. 


From coke.. . . 


45.8 


45-7 


2.0 


4.0 


2.0 


0.5 


— 


O.57 


From bit. coal 


34.O 


41.9 


7.5 


5-4 


9.2 


I.I 


0.9 


— 



Fischer % states that 1 ton of coke gives about 36 
thousand cubic feet of gas, equivalent to 42 per cent 
of the value of the coal. From 1 ton of bituminous 
coal about 51 thousand cubic feet of gas of 360 B.T.U. 
heating power are obtained, or an efficiency of nearly 
62 per cent.§ 

* Suction gas producer. 

f Humphrey, Jour. Soc. Chem. Industry, 20, 107 (1901); ibid., 16, 

522(1897. 
J Taschenbuch fur Feuerungs-Techniker, p. 27. 
§ Slocum, J. Soc. Chem. Industry, 16, 420 (1897). 



66 



GAS AND FUEL ANALYSIS. 



Coal or Illuminating Gas was formerly produced 
by the distillation of bituminous coal ; it is at present 
largely made by the enriching of water-gas. " Gas- 
oil," a crude naphtha, is blown into the water-gas 
generator and changed to a permanent gas by the 
heat. It is of the following composition : 



H CH 4 CO C a H 4 CO a N O Sp. Gr. 

Coal gas 47.O 40.5 6.0 4.0 0.5 1.5 0.5 0.4 

Enriched water-gas 27.9 25.9 25.3 15.0 2.9 3.0 0.0 0.6 

One ton of coal gives about 10 thousand cubic feet of 
gas, or about 20 per cent of the heating value of the 
coal. 

Heating Value of these Gases. 

The following table, mainly from Slocum,* gives an 
idea of the comparative value of the gases: 



Name of Gas. 

Oil 

Natural 

Enriched water 

Coke-oven 

Coal 

Blue water 

Heating (coke-oven). 

Bit. coal water 

Mond producer 

Siemens producer.... 



B. T. U. per 
Cu. Ft.t 

I350 
980 



700 
686 
600-625 
500 
367 
342 
156 
137 



Yield. 

77 cu. ft. 
per gal. 



Thousand Ft. 
per Ton. 

40 % 
5 
10 

5 

5 

5i 

160 

170 



Air Required /or 
Combustion 
per Cu. Ft. 



9.80 



5.65 



2.97 
1.25 



*Slocum, J. Soc. Chem. Industry, 16, 420(1897). 

f Determined with the Junkers calorimeter. 

% 168-200 gallons of " gas-oil " are also required, 



• CHAPTER VIII. 1 

METHODS OF ANALYSIS AND DETERMINATION 
ON THE HEATING VALUE OF FUEL. 

SAMPLING. 

A FEW representative lumps or shovelfuls are taken 
from each barrow or from various points in the pile 
in boiler tests. Shovelfuls of coal should be taken at 
regular intervals and put into a tight covered barrel 
or some air-tight receptacle, and the latter should be 
placed where it is protected from the heat of the fur- 
nace.* The lumps are coarsely broken, and the whole 
spread out in a low circular heap. Diameters are 
drawn at right angles in it and opposite quarters taken, 
and treated similarly to the whole sample. The 
operation is continued until a sample of a few pounds 
is obtained. This is roughly crushed and samples 
taken at different points for the moisture determi- 
nation ; it is then further quartered down until a 
sample of ioo grams which passes a 6o-mesh sieve is 
obtained. 

The methods employed in the analysis of fuels are 
largely a matter of convention, various methods giving 
varied results ; for example, it is well-nigh impossible 
to obtain accurately the percentage of moisture in 
coal, as when heated sufficiently- hot to expel the 
water some of the hydrocarbons are volatilized. 

Moisture. — Dry one gram of coal in an open cru- 

* Report of Committee on Coal Analysis, J. Am. Chem. Soc, 
21, Ili6 et seq. (1899). 

67 



68 GAS AND FUEL ANALYSIS, 

cible at I04°-I07° C. for one hour. Cool in a desic- 
cator and weigh covered. Where accuracy is required, 
determinations must also be made on the coarsely 
ground sample ; this latter result is to be regarded as 
the true amount and corrections applied to all deter- 
minations where the powdered sample is used.* f 

Volatile Combustible Matter and Coke.* — Place 
one gram of fresh, undried powdered coal in a platinum 
crucible having a tightly fitting cover. Heat over the 
full flame of a Bunsen burner for seven minutes by 
the watch. The crucible should be supported on a 
platinum triangle with the bottom six to eight centi- 
meters above the top of the burner. The flame 
should be fully twenty centimeters high when burning 
free, and the determination should be made in a place 
free from drafts. The upper surface of the cover 
should burn clear, but the under surface should remain 
covered with carbon. To find "Volatile Combusti- 
ble Matter " subtract the per cent of moisture from 
the loss found here. The residue in the crucible 
minus the ash represents the Coke or Fixed Carbon. 

Certain non-coking coals suffer mechanical loss 
from the rapid heating. 

Carbon and Hydrogen. — These are determined by 
burning the coal in a stream of air and finally in 
oxygen, the products of combustion, carbon dioxide 
and water, being absorbed in potassium hydrate and 
calcium chloride. 

Apparatus Required. — Combustion-furnace similar 
to that shown in Fig. 15. Combustion-tube filled. 

* Report of Committee on Coal Analysis, loc. cit. 

f Sec also an article by Hale, Proc. Am. Soc. Mech. Eng. 1S96, 



FUEL ANALYSIS— HEATING VALUE. 



69 




Fig. 15. — Combustion-Furnace. 



Potash-bulbs with straight chloride of calcium tube 
filled. Chloride of calcium tube filled. Oxygen- 
holder, drying and purifying apparatus. Porcelain 
boat, desiccator, tongs, i-inch rubber tubing. Ana- 
lytical balance. 

The combustion-tube is of hard glass, \ inch in in- 
ternal diameter and 36 inches long, closed with per- 
forated rubber stoppers. One end — called the front 
end — is filled with a layer of copper oxide 12 inches 
long, held in place by plugs of asbestos coming 
within 4 inches of the stopper. In coals rich in sul- 
phur the oxide is partially replaced by a layer of 
chromate of lead 2 inches long. The position of the 
boat containing the coal is immediately behind this 
copper oxide; behind the boat is placed an oxidized 
copper gauze roll, 6 inches long. Before making the 
combustion, the tube and contents should be heated 
to a dull red heat in a stream of oxygen freed from 
moisture and carbon dioxide by the purifying appa- 



JO GAS AND FUEL ANALYSIS. 

ratus, to burn any dust and dry the contents; it is 
then ready for use. 

The potash-bulbs are an aggregation of five bulbs, 
the three lowest filled with potassium hydrate of 1.27 
sp. gr., the other two serving as safety-bulbs, pre- 
venting the liquid from being carried over into the 
connectors. They should be connected further with a 
chloride of calcium tube to absorb any moisture carried 
away by the dry gas. When not in use they should 
be closed with connectors carrying glass plugs. Before 
weighing they should stand at least fifteen minutes in 
the balance-room to attain its temperature ; the weight 
should be to milligrams and without the connectors. 

The chloride of calcium tube is of U form, provided 
with bulbs for the condensation of the water; the 
granular calcium chloride is kept in place by cotton 
plugs, and the stopper neatly sealed in with sealing- 
wax. As calcium chloride may contain oxide which 
would absorb the carbon dioxide formed, a current, of 
dry carbon dioxide should be passed through the tube 
and thoroughly swept out by dry air before use. 

The chloride of calcium tube like the potash-bulbs 
should be placed in the balance-room fifteen minutes 
before weighing and, if the balance-case be dry, may 
be weighed without the connectors. It should be 
weighed to milligrams. 

The oxygen-holder may be like the Muencke aspi 
rator, Fig. 14. The oxygen should be purified by 
passing through potassium hydrate and over calcium 
chloride. 

Operation. — The front stopper of the combustion- 
tube is slipped carefully upon the stem of the chloride 



fuel analysis— heating value. 71 

of calcium tube and this connected to the potash- 
bulbs; 0.2 to 0.3 gram of the coal is carefully 
weighed into the porcelain boat (to o. 1 mg.), the roll 
removed, and the boat inserted behind the layer of 
copper oxide, and the roll and stopper replaced. 
The tube is now ready to be heated. 

The front of the copper oxide is first heated, the 
heat being gradually extended back; at this time the 
rear end of the copper roll is heated and a slow cur- 
rent of purified air passed through. This method 
of gradual heating of the tube is followed until the 
layer of copper oxide and the rear portion of the roll 
are at a dull red heat. Heat is now cautiously applied 
to the coal and the current of air slackened. The 
volatile matter in the coal distils off, is carried into 
the layer of copper oxide and burned; the carbon 
dioxide formed can be seen to be absorbed by the 
potassium hydrate. When this absorption almost 
ceases, oxygen is turned on and the coal heated until 
it glows. The stream of oxygen should be so regulated 
as to produce but two bubbles of carbon dioxide in 
the bulbs per second. If the evolution be faster, the 
gas is not absorbed. When the coal has ceased glow- 
ing, oxygen is allowed to pass through the apparatus 
until a spark held at the exit of the last chloride of 
calcium tube (on the bulbs) re-inflames; the oxygen is 
allowed to run for fifteen minutes longer. The current 
of oxygen is now replaced by purified air, and the 
heat moderated by turning down the burners and 
opening the fire-clay tiles; the air is allowed to run 
through for twenty minutes to thoroughly sweep out 
all traces of carbon dioxide and moisture. The bulbs 



J2 GAS AND FUEL ANALYSIS. 

and U tube are disconnected, stopped up, allowed to 
stand in the balance-room, and weighed as before. 
The increase in weight in the bulbs represents the 
carbon dioxide formed; this multiplied by the factor 
O.2727 gives the carbon. Similarly the increase in the 
U tube, minus the water due to the moisture in the 
coal, represents the water formed, one ninth of which 
is hydrogen. 

Notes. — At no time in the combustion should any 
water appear near the copper roll, as it is an indication 
that the products of combustion have gone backward 
into the purifying apparatus and hence are lost. Such 
analyses should be repeated. Should moisture appear 
in the front end, it may he gently heated to expel it. 
Both ends of the tube should be frequently touched 
with the hand during the combustion, and should be 
no hotter than may be comfortably borne, as the 
stoppers give off absorbable gases when highly heated. 
Care should be taken not to heat the tube too hot, 
fusing the copper oxide into and spoiling it. One 
tube should serve for a dozen determinations. It 
should not be placed upon the iron trough of the 
furnace, but upon asbestos-paper in the trough, to 
prevent fusion to the latter. 

As will be seen, the execution of a combustion is 
not easy, and should only be intrusted to an experi- 
enced chemist. The results obtained are usually 0.1 
per cent too low for carbon and a similar amount too 
high for hydrogen. 

Ash. — This is determined by weighing the residue 
left in the boat after combustion, or by completely 



FUEL ANALYSIS— HEATING VALUE, 73 

burning one gram of the coal contained in a platinum 
dish; often a stream of oxygen is used. 

Nitrogen is determined by Kjeldahl's method, 
which consists in digesting the coal with strong sul- 
phuric acid, aided by potassium permanganate, until 
nearly colorless. The nitrogenous bodies are changed 
to ammonia, which forms ammonium sulphate and 
may be determined by rendering alkaline and distil- 
ling the solution. 

Sulphur is determined by Eschka's method, con- 
sisting in heating for an hour one gram of the coal 
mixed with one gram of magnesium oxide and 0.5 
grm. sodium carbonate in a platinum dish without stir- 
ring, using an alcohol-lamp, as gas contains sulphur. 
It is allowed to cool and rubbed up with one gram of 
ammonium nitrate and heated for 5 to 10 minutes 
longer. The resulting mass is dissolved in 200 cc. of 
water evaporated to 150 cc, acidified with hydro- 
chloric acid, filtered, and sulphuric acid deter- 
mined in the filtrate in the usual way with barium 
chloride. 

Oxygen is determined by difference, there being 
no direct method known. 

The analysis of gaseous fuels has already been de. 
scribed in Chapter V„ 



74 GAS AND FUEL ANALYSIS. 

DETERMINATION OF CALORIFIC POWER OF SOLID 
AND LIQUID FUEL. 

a. Direct Methods. 

Many forms of apparatus have been proposed 
for this purpose; few, however, with the exception 
of those employing Berthelot's principle — of burning 
the substance under a high pressure of oxygen — 
have yielded satisfactory results. The apparatus of 
William Thomson,* and also that of Barrus, in which 
the coal is burnt in a bell-jar of oxygen, while usually 
yielding results within 3 per cent of the calculated 
value, yet they may vary as much as 8 per cent 
from that value. f Unless a crucible lined with 
magnesia be used, or the sample mixed with bitumin- 
ous coal, it is inapplicable to certain semi-bitumin- 
ous and anthracite coals, as the ash formed over 
the surface prevents the combustion of the coal 
beneath it. 

Fischer's calorimeter^: is similar in principle, but is 
claimed to give very good results. § 

Lewis Thompson's calorimeter, in which the coal is 
burnt in a bell-jar by the aid of oxygen furnished by 
the decomposition of potassium chlorate or nitrate, is 
open to several objections, the chief of which are: 
I . The evolution of heat due to the decomposition of the 



* Thomson, Jour. Soc. Chemical Industry, 5, 581. 
f Ibid., 8, 525. 

\ Zeit. f. angewandte Chemie, 12, 351. 

§ Bunte, Jour. f. Gasbcleuchtung und Wasserversorgung, 34, 
21, 41. 



FUEL ANA LYSIS— HEATING VALUE. 7j> 

oxidizing substance used. 2. Loss of heat due to 
moisture carried off by the gases in bubbling through 
the water. The results which it gives must be in- 
creased by 15 per cent.* 

Hempel's apparatus f makes use of the Berthelot 
principle: the coal must be compressed into a cylindei 
for combustion — a process to which every coal is not 
adapted — only applicable to certain varieties of 
bituminous and brown coal. The mixture with the 
coal of any cementing or inflammable substance to 
form these cylinders carries with it the necessity of 
accurately determining its calorific power beforehand. 

The best apparatus for the purpose is probably that 
of Mahler, \ § modified by Holman, Williams, ard 
Norton, the modifications consisting in replacing the 
enamel lining by electroplating the inside with gold 
and in improved methods of making the apparatus 
tight. 

The Mahler apparatus, Fig. 17, consists of a mild- 
steel cylinder i?, with walls half an inch thick, narrowed 
at the top for connection by a screw-joint with the 
cover carrying the vessel C to contain the coal. This 
cylinder or bomb is placed inside the calorimeter D, 
and this inside a jacket A. At the right is shown a 
portion of the oxygen-cylinder and the gauge. 

For the following directions for its use the author 
is indebted to the kindness of Professor Silas W. 
Holman of the Institute of Technology. 

* Scheurer-Kestner Jour. Soc. Chemical Industry, 7, 869. 
f Hempel, " Gasanalytische Methoden," p. 347. 
% Mahler, Jour. Soc. Chemical Industry, 11. 840. 
§ Mayer, Stevens Indicator, (1895) 134. 



;6 



GAS AND FUEL ANALYSIS. 



Preparation of Bomb. — Remove the ring upon 
which it sits in the calorimeter. 

Wash out the bomb. It need not be dry. Leave 
cover off. 

See that the lead-ring washer P, Fig. 16, is in good 
condition. Unless its upper surface 
is fairly smooth the cover cannot be 
tightly closed. Repeated screwing 
on of the cover raises a burr of lead. 
When this becomes noticeable it must 
be removed by cutting with a knife- 
blade. If there is difficulty in mak- 
ing the cover tight, it is most likely 
to be due to this cause. 

Grease the screw 5 upon the out- 
side of the bomb slightly with tallow 
or a heavy oil, but be sure that none 
of the grease gets beyond the lead 
washer. 

Secure the bomb very firmly in the 
heavy clamp on the table. 
Place the top on a ring or in a clamp of a lamp-stand 
and in an upright position. 

Put in position the platinum tray C and the rod E 9 
Fig. 17. 

Twist on the loop of ignition-wire (fine platinum 
or iron). This must make good electrical contact 
with both E and the pan or its supporting rod. 
Failing this the current will not flow to fuse the wire. 
Failure to ignite is almost always traceable to this 
cause. 

Pour into the tray a known weight of the substance 




Fig. 16— Mahler's 
Bomb. 



FUEL ANALYSIS— HEATING VALUE, 



77 



to be burned. If this be coal, slightly over one gram 
should be used. It is usually best inserted from a 
small test-tube weighed before and after, with due 
precautions against loss. 

The ignition-wire should dip well into the coal. 

The fineness required in the combustible depends 



h^g^l 




Fig. 17. — Mahler's Apparatus Complete. 

upon its nature. Anthracite coal should be in a very 
fine powder. Trial will show whether any unburned 
grains remain, indicating that the combustible is too 
coarse. 

The standard which carries the pressure-gauge 
should be screwed to the table near the bomb-clamp, 
and the oxygen cylinder must be placed near by so 
that the three may be easily connected by the flexible 
copper tube. 



78 GAS AND FUEL ANALYSIS. 

The top carrying the charge is then cautiously (to 
avoid loss of charge by jarring or draft) transferred to 
the bomb and screwed carefully home. The lifting is 
best done by hooking the fingers beneath the milled 
head at the top of the valve-screw R. The top must 
be set up hard by the wrench which takes the large 
nut cut on the cover. In setting this up it is desirable 
to use no more force than is necessary to secure a gas- 
tight bearing of the tongue of the cover against the 
lead washer P. Just the force required can only be 
learned by experience, but it is always considerable. 
A slight leak is unimportant, but it is not difficult to 
secure a tight seal if the lead washer be kept in good 
condition. 

To fill with oxygen proceed as follows: 

Screw down the valve-screw R gently to close the 
valve. Connect the copper tube to the oxygen-tank 
gauge, and to the bomb at N. See that there are 
leather washers at the joints. Turn the connecting 
nuts firmly but not violently home. The connections 
to the oxygen-tank and gauge are usually left undis- 
turbed, and only that at N has to be made each time. 

It is now necessary to test for leakage in the con- 
nections. To do this, as R is closed, it is only neces- 
sary to open the oxygen-tank cautiously by means of 
its wrench until the gauge indicates 5 or 10 atmos- 
pheres and then close it. As the tank when freshly 
charged has a pressure of 120 atmospheres, and the 
gauge reads only to 35 atmospheres, care must be used 
in all manipulations not to overstrain the gauge, also 
avoid suddenly releasing the pressure on the gauge. 
When this pressure is on, any leak in the connections 



FUEL ANALYSIS— HEATING VALUE, 79 

will be indicated by a drop in the gauge reading. If 
a leak exists, it must be removed or rendered extremely 
slow before proceeding further. It is most likely to 
be found in the joints, which must be tightened one 
by one until the leak stops. 

Now to fill the bomb it is next necessary to open 
R. This could be done by merely turning back the 
milled head, or the nut just above it. But as this 
would put a twist into the copper connecting-tube 
(which many times repeated would break it), the better 
way is, holding one wrench in each hand, to loosen 
the connecting nut above N by a half-turn, holding R 
by the wrench and nut, then to turn the nut open 
a half-turn or until it is again tight in. This leaves 
the connections tight and R open into the bomb. The 
oxygen is then turned slowly on, and the bomb 
gradually fills. If a gram of coal is to be burned, a 
pressure of 25 atmospheres gives the proper amount of 
gas in the bomb. Note that the valve R and the inlet- 
tube have small borings. Thus the inflow of gas will 
be slow and the pressure in the connecting-tube will 
be higher than in the bomb. If, therefore, the tank 
be closed quickly, the gauge-reading will fall somewhat 
until these pressures equalize, and will then remain 
stationary unless there is a leak. The tank-cock must 
always be kept well under control to avoid overcharg- 
ing either gauge or bomb. 

When the bomb is full, close first the tank-cock. 
Then, to close R y put the wrenches on the nuts and, 
holding one from turning, set the other down until R 
is tight, but not too tight. Avoid straining R, which 
closes tight very easily. By this method the copper 



8o 



GAS AND FUEL ANALYSIS. 



tube is not twisted. There is of course a slight leak 
of gas from the bomb after N leaves the nut and 
before R is closed, but the time required for the half- 
turn is so short and the outflow so slow that the loss 
is insignificant. There is no need to hurry in this 
operation. Be deliberate and careful of the apparatus. 
A valve like R is a nice piece of workmanship, and to 
endure much usage it must be treated with care. 

The bomb is now ready to be undamped and set 
into the ring preparatory to transfer to the calorimeter. 
It can be left standing indefinitely, but must be 
handled with caution (best by lifting with fingers 
beneath R, to avoid spilling the charge). 

Preparation of Calorimeter. — The outer jacket of 
the calorimeter should be filled with water at about 
the room temperature or a few degrees higher. If 
left standing from day to day it will usually be nearly 
enough right. It is well to stir it (blow air through 
it) somewhat before beginning work, if it has stood for 
some time. 

Be sure that the inner surface of this jacket, i.e., 
the one which is next the calorimeter, is thoroughly 
dry, and do not let any water spill into it — or remove 
it if it does so. 

Thoroughly dry the outer surface of the calorimeter 
and keep it so. Moisture depositing on or evaporating 
from the surface of the calorimeter is sure to cause an 
irregular error which may spoil otherwise good work. 

Put the calorimeter in place. Transfer the bomb to 
it, and adjust the stirrer so that it works properly. 

Pour in the proper amount of water, about 2.25 



FUEL ANALYSIS— HEATING VALUE. 8l 

liters, at a suitable temperature, best by using marked 
flasks carefully calibrated beforehand. 

Insert the thermometer. 

See that the electrical attachments are ready for 
instantaneous use. The whole is then ready for the 
combustion. 

Combustion Observations. — With apparatus all in 
place run the stirrer briskly and continuously until 
the completion of the work. Allow about five minutes 
for everything to come to a normal condition. Then 
take temperature readings to at least o.oi° at each 
quarter minute for at least five minutes. Record the 
times (h. m. s.) and corresponding thermometer-read- 
ings, thus: 



Time. 


Temp. 


Remarks. 


2 h jgm s 


I5°.2 4 


After 5 m stirring 


15 


.24 




30 


.25 




45 


.25 




16 


.25 




15 


.26 




30 


.26 




25 


— 


Coal ignited 


15 


15.6 




30 


•9 




45 


16.2 




26 


•5 




etc. 


etc. 





Exactly at the beginning of a noted minute close 
the electric circuit through the fuse-wire. If the 
arrangements are right, this will cause the coal to 
ignite at once and the combustion is almost instan- 
taneous. Owing to the time required to transmit the 



82 GAS AND FUEL ANALYSIS. 

heat through the bomb to the water, the temperature, 
however, will continue to rise for two or three minutes. 
Keep up the steady stirring and the quarter-minute 
temperature-readings for at least ten minutes after 
ignition, recording as above. One or two observations 
may be unavoidably lost before and after ignition, but 
this does not materially affect the results. The read- 
ings during the rapid rise are also less close, 

As soon as the rise begins to slow down, however, 
the hundredths of a degree must again be secured. 
This makes a series of observations of 15 to 20 
minutes' duration. The use of the readings to obtain 
the cooling correction and the corrected rise of tem- 
perature of the calorimeter is given under the heading 
" Cooling Correction ' * farther on. 

This completes the observations unless it is desired 
to test the character of the products of combustion* 
The bomb should now be opened and rinsed, as the 
nitric acid formed by the oxidation of the nitrogen in 
the coal and air attacks the metallic lining unless it be 
of gold. Also the top is more easily unscrewed at 
first than later. Leave the top off. 

Before unscrewing the top of the bomb be sure to 
open the valve R to relieve the presure. 

Heat Capacity of Bomb and Calorimeter. — The 
heat capacity of the bomb may be found: 

1. From the weights and assumed specific heats of 
the parts. 

2. By raising the bomb to an observed high tem- 
perature and immersing in water, i.e., by the usual 
" method of mixtures/' 

3. By burning in it a substance of known heat of 



FUEL ANALYSIS— HEATING VALUE. 83 

combustion, such as pure naphthaline, and calculating 
back to find the heat capacity of the bomb. 

The first method is not reliable. Errors of several 
per cent may enter in the assumed specific heats. 

The second method is very difficult of exact per* 
formance, owing to the size and form of the bomb. 

The third method is bv far the most reliable, but of 
course depends on the correctness of the assumed heat 
of combustion of the substance used. That of naphtha- 
line has been so well determined by Berthelot and 
others,* and the substance is so easily and cheaply 
obtained in a pure state, that dependence can be 
placed on the results. This method has the great 
advantage that it involves the use of the apparatus in 
precisely the same way as in subsequent determina- 
tion, so that any systematic errors of method tend to 
cancel one another. It also determines at the same 
time the heat capacity of the calorimeter and stirrer 
just as used. 

The capacity of the calorimeter and stirrer may 
best be determined in connection with that of the 
bomb by the third method just described. Otherwise 
it may be found by the first method, or by a method 
similar to the second, viz. , by pouring into the calorim- 
eter when partly full water of a known temperature 
different from that of the water in the calorimeter, 
noting all temperatures and weights. This last 
method, however, is very unsatisfactory in practice 
owing to the small heat capacity of the calorimeter 
and to the losses of heat in pouring the water, etc. 

* I gram of naphthaline evolves 9692 C. This is the average of 
150 determinations by four different obervers. 



84 GAS AND FUEL ANALYSIS. 

A general expression for computing the heat of 
combustion from the bomb observations is as follows: 
Let n represent the number of grams of combustible, 
H the heat of combustion sought, J^the weight of 
water in the calorimeter, and k the heat capacity, 
or water equivalent, of bomb, calorimeter, stirrer, 
thermometer, etc. ; t x and / 2 represent the initial and 
final temperatures of the water. Then 

nH = W{t 2 — /,) -f k{t % -~ /,)> 
whence 

H= l -{W+k){t i -t 1 ). 

This expression is exact if t %l is corrected for loss by 
cooling as described in the methods for " Cooling 
Correction,' ' p. 85, 

The value of k may be determined by either of the 
following methods; a simplification may, however, be 
introduced which will save much labor if an accuracy 
of not more than about one per cent is sought, pro- 
vided that k is found by burning naphthaline or other 
known substance. Use enough of this substance to 
cause about the same rise, / 2 — /, , (within i°) as will be 
caused by one gram of coal. Omit the cooling correc- 
tion entirely, using for t 2 the maximum temperature 
attained. Then compute k\ this value will be erro- 
neous by a small amount owing to the neglect of the 
correction. Now in subsequent measurements on coal 
also neglect the cooling correction, using for t 2 the 
maximum observed temperature as before, thus leav- 
ing an error in / 2 . Since the rise / a — /, in both cases 
will be nearly the same, the error in k will almost 



FUEL ANALYSIS— HEATING VALUE. 85 

exactly affect that in t 2 in the coal-test, and the result- 
ing value of H will be nearly free from this error. 
This method of course implies that W is nearly con- 
stant and that t x is systematically arranged to be either 
about at the air-temperature or a definite amount 
below it, as described under " Cooling Correction/' 
so that the cooling loss is about the same. The time- 
interval from t x to / 2 must for the same reason be 
nearly constant in all cases. 

Cooling Correction. — In all careful calorimetric 
work, one of the most troublesome sources of error is 
the loss or gain of heat by the calorimeter from its 
surroundings. This loss or gain is due to radiation, 
to air-convection currents, and to evaporation or con- 
densation. Unavoidable irregularities in the condi- 
tions and the smallness of the quantities to be measured 
render the amount of the correction variable and its 
determination uncertain. Many methods of making 
the correction have been proposed. One of the best 
of these is the first of the two given below, but the 
second, although a little more troublesome in the 
execution of the work, appears to be more trustworthy 
in its results. The second method is to be used. 

First Method. — This is described in the Physical 
Laboratory Notes, I,* under " Specific Heat of Solids." 
In this method the water at the outset should be at 
such a temperature that it is gaining very slowly. 
For an open calorimeter this is about i° or 2° below 
the air-temperature, but varies with circumstances. 
Water which has been long standing in the room is 
generally about right. 

Second Method. — For the discussion and detail? 

* Obtainable from A. D. Machlachlan, Bookseller, Boston. 



86 



GAS AND FUEL ANALYSIS. 



reference may be had to an article by Professor Holtnan 
in Proc. American Academy of Arts and Sciences, 1895, 
p. 245 ; also in The Technology Quarterly, 8, 344. 

Parr's Calorimeter.* — This " has the advantage of 
operating without an oxygen gas supply ; its manipu- 
lation is simple and the extraction of the heat rapid, 
owing to the compact mass in which the heat is gen- 
erated. It is especially adapted to soft coal, and 
while designed for technical purposes, its factor of 
error is well within 0.5 per cent." " It depends for its 
action upon the liberation of oxygen from a compound 
which shall in turn absorb the products of combustion, 

conditions admirably met in 
sodium peroxide; this ob- 
viates the necessity of pro- 
viding for an outlet for those 
gases and also any loss aris- 
ing from the heat they 
might carry off/' 

" A, Fig. 18, is the calor- 
imeter of about two liters 
capacity, insulated by two 
outer vessels of indurated 
fiber, B and C, so placed as 
to provide further insulation 
by the air-spaces b and c. 
Fig. 18.— Parr's Calorimeter. The cover is double, to cor- 
respond, with an air-space between, the two parts 
being connected for convenience in handling. The 
cartridge D has a capacity of about 25 cc. ; it rests 
on a pivot below, extends through the covers, and has 
a small removable pulley at the end. Turbine wings 




* Parr, J. Am. Chem. Soc, 22, 646 (1900). 



FUEL ANALYSTS— HEATING VALUE. %*] 

fastened to spring clips are placed on the cartridge, 
and a short cylinder E, open at both ends, is provided 
for directing the current set up by rotation of the 
vanes attached to the cartridge. The stem G of the 
cartridge is so arranged as to permit the passage of a 
short piece of No. 12 copper wire to ignite the charge ; 
it is provided with a valve D at the lower end to pre- 
vent the escape of the enclosed air." 

Manipulation. — One gram of coal ground to pass a 
ioo-mesh sieve, dried at 105 °, is put into the cartridge, 
16-18 grams of sodium peroxide added, the top 
screwed on, and the whole shaken to thoroughly mix 
the contents. The peroxide should be fine enough to 
pass a 25-mesh sieve. The cartridge is tapped to 
settle the charge to the bottom, placed in the calor- 
imeter, two liters of water poured in, and rotated 50 
to 100 revolutions per minute. The water should be 
3 to 4 degrees lower than the room temperature. 
When the temperature has become constant, the 
thermometer is read, a hot wire dropped down 
G, igniting the charge, which burns completely. 
The extraction of the heat is effected in about five 
minutes; the reading of the maximum temperature 
is taken and the calculations made as follows : The 
rise of temperature is corrected, first, for that produced 
by the hot wire; this amounts to 0.006 C. per i inch 
of No. 12 copper wire: second, for the heat produced 
by the combination of the sodium peroxide with the 
carbon dioxide and water formed by the combus- 
tion ; this amounts to 27 per cent of the total indi- 
cated heat. If C = the heat of combustion of the 
coal, C the calories indicated, t the rise of tempera- 
ture, and w the water employed, then 



88 GAS AND FUEL ANALYSIS. 



„, C X 2 7 



oo 



a = (/ — 0.006 ) x w, c = o — : — 

C = (t - 0.006 ) X w X 0.73 



Notes. — Instead of using a gram of coal some prefer 
to use half this quantity, mixing it thoroughly and 
rapidly with the peroxide in a watch-glass with a spatula 
and transferring it to the combustion-chamber. 

Ignition by an electrically heated platinum wire is 
to be preferred to that by dropping a hot copper wire 
into the mixture. Accidents have been caused from 
the failure of the valve to work. 

The combustion-chamber should be perfectly dry 
within and without. 

Ashes and coke are difficult of ignition : this can be 
effected by adding a second charge of peroxide with 
half a gram of good coal, the combustion factor of 
which has been determined, and thoroughly mixing 
the charges and repeating the ignition. 

For stirring, the smallest size electric or water 
motor furnishes sufficient power. 

In the formulae w = the water employed -f- the 
water equivalent of the calorimeter. 

Berthier s Method. — Another method of direct 
determination was proposed by Berthier in 1835.* 
It uses as a measure of the heating value the amount 
of lead which a fuel would reduce from the oxide ; in 
other words, it is proportional to the amount of oxygen 
absorbed. 

The method is as follows f : Mix one gram of the 

* Dingler's Polytechnisches Journal, 58, 391. 

f Noyes, McTaggart & C raver, J. Am. Chem. Soc, 17, 847 (1798). 



FURL ANALYSIS— HEATING VALUE. 89 

finely powdered dry coal with 60 grams of oxide of 
lead (litharge) and 10 grams of ground glass. This 
mixing can be done with a palette-knife on a sheet of 
glazed paper; the mixture is transferred to a fire-clay 
crucible (Battersea C size), covered with salt, the 
crucible covered and heated to redness in a hot gas- 
furnace — or the hottest part of the boiler-furnace — for 
15-20 minutes. After cooling, the crucible is broken 
and the lead button carefully cleaned and weighed. 
Multiply the weight of the lead button obtained by 
268.3 calories (or 483 B. T. U.) and divide the prod- 
uct by the weight of coal taken. The result is the 
number of calories per gram or B. T. U. per pound. 
One gram of lead is theoretically equivalent to 234 
calories (C) ; owing to the hydrogen present this factor 
gives results about two per cent too low. The results 
obtained by the author using " horn-pan " scales in one 
case by this method were within 2.8 per cent of those 
yielded by the bomb calorimeter, which are as close 
as those obtained by any calorimeter save Parr's. 
The method would seem worthy of more attention 
than it has received. 



b. Determination of Heating Value by Calculation. 

The method of determination of the heating value 
first described, though exact, has the disadvantages 
that the apparatus is costly and the compressed 
oxygen is not easily obtained. To obviate these, 
it has been sought to obtain the heating value by 
calculation from the chemical analysis, the heating 
value of the constituents being known. This has 
the disadvantage that we have no absolute knowl- 



90 GAS AND FUEL ANALYSIS, 

edge — nay, not even an approximate idea — as to how 
the carbon, hydrogen, water, and sulphur exist in the 
coal, so that any formula must of necessity be quite 
removed from the truth. Dulong was the first to 
propose the method by calculation, and his formula* is 

8ooo£ -f- 345oo(// — \6) 



H = 



ioo 



c, h, and o representing the percentages of carbon, 
hydrogen, and oxygen in the coal. 

Many modifications of this, considering the water 
formed, the heat of vaporization of carbon, or the 
volatile hydrocarbons, have been proposed. 

Bunte f finds that the following formula \ gives results 
varying from -f- 2.8 to — 3.7 per cent: 

8o8o^4- 28800 \h — 2) -f- 2500.? — 6oow 

100 

s and w represent the percentages of sulphur and 
water respectively. It is, however, inapplicable to 
anthracite coal. It would scarcely seem that the 
sulphur would be worth considering unless high, one 
per cent affecting the result but 0.3 per cent. 
Mahler employs the formula* 

8140^ -f- 345oo/z — 3000(0 -f- n) 
100 ' 

o and n representing oxygen and nitrogen, and states 
that it gives results within 3 per cent. 

The results obtained by these formulae for anthracite 
coal are as a rule considerably too low. 

* H burned to liquid water. % H burned to aqueous vapor, 
f Jour, fiir Gasbclcuehtung, 34, 21-26 and 41-47. 



FUEL ANALYSIS— HEATING VALVE, 9 1 

Goutal * has proposed the formula 

_ 8150^ + AM 
~~ 100 

as being more readily applicable than the preceding. 

P represents the calorific power; c t the percentage 
of fixed carbon (coke — ash) ; M, the percentage of 
volatile matter (100 — [coke -f- ash -f- water]) ; A is a 
coefficient which varies with the amount of volatile 
matter M y viz. : 



M -- 


- 2 to 15 


A = 


= 13000 




15 to 30 




1 0000 




30 to 35 




9500 




35 to 40 




9000 



The results upon a series of American coals varied 
less than 2 per cent from those obtained by the 
calorimeter. 

* Revue de chimie ind., 7 (1896), 65 ; abs. in The Analyst, 24, 
107. 



92 GAS AND FUEL ANALYSIS. 

CALORIFIC POWER OF GASEOUS FUEL. 

a. Direct Determination. 

Perhaps the best apparatus for the determination of 
the heating value of gases is the Junkers calorimeter, 
Figs. 1 8 and 19. The following description is taken 




Fig. 18. — Junkers Gas-calorimeter (Section). 

from an article by Kuhne in the Journal of the Society 
of Chemical Industry, vol. 14, p. 631. As will be 



FUEL ANALYSIS— HEATING VALUE. 



93 



seen from Fig. 18, this consists of a combustion-cham- 
ber, 28, surrounded by a water-jacket, 15 and 16, 
this being traversed by a great many tubes. To 
prevent loss by radiation this water-jacket is sur- 




Fig. 19. — Junkers Gas-calorimeter. 

rounded by a closed annular air-space, 13, in which 
the air cannot circulate. The whole apparatus is 
constructed of copper as thin as is compatible with 
strength. The water enters the jacket at 1, passes 
down through 3, 6, and 7, and leaves it at 21, while 



94 GAS AND FUEL ANALYSIS. 

the hot combustion-gases enter at 30 and pass down, 
leaving at 31. There is therefore not only a very 
large surface of thin copper between the gases and the 
water, but the two move in opposite directions, during 
which process all the heat generated by the flame is 
transferred to the water, and the waste gases leave the 
apparatus approximately at atmospheric temperature. 
The gas to be burned is first passed through a meter, 
Fig. 19, and then, to insure constant pressure, through 
a pressure-regulator. The source of heat in relation 
to the unit of heat is thus rendered stationary; and in 
order to make the absorbing quantity of heat also 
stationary, two overflows are provided at the calo- 
rimeter, making the head of water and overflow con- 
stant. The temperatures of the water entering and 
leaving the apparatus can be read by 12 and 43; as 
shown before, the quantities of heat and water passed 
through the apparatus are constant. As soon as the 
flame is lighted, 43 will rise to a certain point and will 
remain nearly constant. 

Manipulation. — The calorimeter is placed as shown 
in Fig. 19, so that one operator can simultaneously 
observe the two thermometers of the entering and 
escaping water, the index of the gas-meter, and the 
measuring-glasses. 

No draft of air must be permitted to strike the ex- 
haust of the spent gas. 

The water-supply tube w is connected with the 
nipple a in the centre of the upper container; the 
other nipple, b, is provided with a waste-tube to carry 
away the overflow, which latter must be kept running 
while the headings are taken. 



FUEL ANALYSIS— HEATING VALUE. 95 

The nipple c through which the heated water leaves 
the calorimeter is connected by a rubber tube with 
the large graduate, d empties the condensed water 
into the small graduate. 

The thermometers being held in position by rubber 
stoppers and the water turned on by e until it dis- 
charges at c, no water must issue from d or from 39, 
Fig. 18, as this would indicate a leak in the calorim- 
eter. 

The cock e is now set to allow about two liters of 
water to pass in a minute and a half, and the gas 
issuing from the burner ignited. Sufficient time is 
allowed until the temperature of the inlet-water 
becomes constant and the outlet approximately so; 
the temperature of the inlet-water is noted, the read- 
ing of the gas-meter taken, and at this same time the 
outlet-tube changed from the funnel to the graduate. 
Ten successive readings of the outflowing water are 
taken while the graduate (2-liter) is being filled and 
the gas shut off. 

A better procedure is to allow the water to run into 
tared 8-liter bottles, three being used for a test, and 
weighing the water. The thermometer in the outlet 
can then be read every half-minute. 
Example. — Temp, of incoming water, 17. 2° 
" " outgoing " 43.8 

Increase, 26. 6° 

Gas burned, 0.35 cu. ft. 
H _ liters water X increase of temp. _ 2 X 26.6 
cu. ft. gas 0.35 

= 152.3C 

From burning one cubic foot of gas 27.25 cc. of 
water were condensed. This gives off on an average 
0.6 C. per cc. 



96 GAS AND FUEL ANALYSIS. 

27.25 x 0.6= 16.3 C; 
152.3 — 16. 1 = 136 C. per cubic foot; 
136 X 3.96823=: 540 B. T. U. 

The calorific power obtained without subtracting 
the heat given off by the condensation of the water 
represents the total heating value of the gas. This is 
the heat given off when the gas is used for heating 
water or in any operation where the products of 
combustion pass off below I00° C. The net heating 
value represents the conditions in which by far the 
greater quantity of gas is consumed, for cooking, 
heating and gas engines, and is the one which should 
be reported. It should, however, be corrected, as 
shown on page 99, to the legal cubic foot, that is, 
measured at 30 inches barometric pressure, and 6o° 
F. saturated with moisture. 

The apparatus has been tested for three months 
in the German Physical Technical Institute with hy- 
drogen, with but a deviation of 0.3 per cent from 
Thomson's value. This value may vary nearly that 
amount from the real value owing to the method 
which he employed. 

b. By Calculation. 

Oftentimes it may be impracticable to determine 
the heating value of gases directly; in such cases 
recourse must be had to the calculation of its calorific 
power from volumetric analysis of the gas. 

To this end multiply the percentage of each con- 
stituent by its number as given in Table IV, and the 
sum of the products will represent the British Thermal 
Units evolved by the combustion of one cubic foot of 



FUEL ANALYSIS— HEATING VALUE. 97 

the gas.* It is assumed that the temperature of the 
gas burned and the air for combustion is 6o° F., and 
that of the escaping gases is 328 F., that correspond- 
ing to the temperature of steam at 100 pounds abso- 
lute pressure. 

As has been already stated, column 3 in Table IV 
is based upon the assumption that the gas, and air for 
its combustion, enter at 6o° F., and the products 
of combustion leave at 328°F. ; in column 4 it is 
assumed that the entering temperature of both gas 
and air is 32 F., and the combustion-gases are cooled 
to 32 F. In case these conditions are varied, the 
amount of heat which the gas and air bring in must be 
determined; this is found in the usual way by multi- 
plying the proportionate parts of 1 cubic foot, as 
shown by the analysis, by the specific heat of the gas, 
and this by the rise in temperature (difference between 
observed temperature and 32 F.). The quantity of 
air necessary for combustion is found by multiplying 
the percentage composition of the gas by the number 
of cubic feet necessary for the combustion of each 
constituent. 

An example will serve to make this clear. The 
analysis of Boston gas is as follows:* 



CO a "Illuminants." O CO 


CH 4 


H 


N 


2.9 15.O O.O 25.3 


25.9 


27.9 


3.0 


Or in one cubic foot there are 









* H. L. Payne, Jour. Analytical and Applied Chem., 7, 230. 
f Jenkins, Annual Report Inspector oi Gas Meters and Illuminating 
Gas, 1896, p. 11. 



98 GAS AND FUEL ANALYSIS. 

.029 C0 2 259 CH 4 

.150 " illuminants " 279 H 

.253 CO.. 030 N 

Let us assume that the gases, instead of passing 
out at a temperature of 328 F., leave at the same 
temperature as that of the chimney-gases, p. 29, 250 
C. or482° F. 

The calculation of the heat carried away is similar 
to that there given. 
0.15 cu. ft. of " illuminants " produces, Table III, 

0.3 cu. ft. C0 2 and 0.3 cu. ft. steam; 
0.253 cu - ft. of carbonic oxide produces .253 cu. ft. 

C0 2 ; 
0.259 cu. ft. methane produces 0.259 cu - ft- C0 2 an d 

.518 cu ft. steam ; 
0.279 cu. ft. hydrogen produces .279 cu. ft. steam. 

From the combustion of the gas there results .812 
cu. ft. C0 2 , 1.097 cu. ft. steam, and 5.90 X 79.08 or 
4.665 cu. ft. N. 

The quantity of heat they carry off is as follows: 

Vol. Vol. Sp. Ht. Rise. B.T.U. 

C0 2 812 X .027 X 45o= 9-9 

N 4.66 X .019 X 45°= 39-9 

Excess of air.. 1.2 X .019 X 450 = 10.2 

Steam 1.097 X .0502 X 1229 = 67.7 

Total heat lost = 127.7 



FUEL ANALYSIS— HEATING VALUE, 99 

The loss due to the steam is found by multiplying 
the weight of steam found by the " Total Heat of 
Steam/ ' as found from Steam Tables.* The tables, 
however, do not extend beyond 428 F. ; it can be 
calculated by the formula 

Total heat = A == 1091.7 -f- °-3°5(^ — 3 2 )- 

One cubic foot of hydrogen when burned yields 
.0502 lbs. of water. 

The heat generated by the combustion of the gas is 
found by multiplying its volume by its calorific power, 
Table IV. 

" Illuminants" 0.15 X 2000.0 = 300.0 B.T.U. 

CO 0253X 341.2= 86.3 

CH 4 0.259 x 1065.4 = 276.0 

H 0.279X 345-4= 96.3 

Heat generated by the gas. 758.6 B.T.U. 

Total heat lost (p. 98) 127.7 

630.9 B.T.U. 

This figure, 630.9 B.T.U., represents the heating 
power of one cubic foot of the gas measured at 62 F,, 
and is consequently too small ; its heating value at 
32 F. is represented by 

492 ^~ 2 3 ° X 630.9, or 669.1 B.T.U. 

* Peabody's Steam Tables. 

LOFC. 



APPENDIX, 



TABLE I. 

TABLE SHOWING THE TENSION OF AQUEOUS VAPOR AND ALSO THE 
WEIGHT IN GRAMS CONTAINED IN A CUBIC METER OF AIR 
WHEN SATURATED. 

From 5° to 30 C. 



Temp. 


Tension, 
mm. 


Grams. 
6.8 


Temp. 
14 


Tension, 
mm. 

II. 9 


Grams. 
I2.0 


Temp. 
23 


Tension, 
mm. 


Grams. 


5 


6-5 


20,9 


20.4 


6 


7.0 


7-3 


15 


12-7 


12.8 


24 


22.2 


21.5 


7 


7-5 


7-7 


16 


13-5 


13.6 


25 


23.6 


22.9 


8 


8.0 


8.1 


17 


14.4 


14.5 


26 


25.O 


24.2 


9 


8.5 


8.8 


18 


15.4 


I5-I 


27 


26.5 


25.6 


10 


9.1 


9.4 


19 


16.3 


16.2 


28 


28.1 


27.O 


11 


9.8 


10. 


20 


17.4 


17.2 


29 


29.8 


28.6 


12 


10.4 


10.6 


21 


18.5 


18.2 


30 


31-5 


29.2 


13 


11. 1 


n-3 


22 


19.7 


19-3 









TABLE II. 

VOLUMETRIC" SPECIFIC HEATS OF GASES.* 



Air 0.019 

Carbon dioxide 0.027 

Carbonic oxide 0.019 

Hydrogen 0.019 



" Illuminants " 0.040 

Methane 0.027 

Nitrogen 0.019 

Oxygen 0.019 



The " volumetric " specific heat is the quantity of heat neces- 
sary to raise the temperature of one cubic foot of gas from 32 F. 
to 33 F. 



* H. L. Payne, Jour, Anal, and Applied Chem., 7, 233. 

100 



TABLES. 



IOI 



TABLE III. 



THE VOLUME OF OXYGEN AND AIR NECESSARY TO BURN ONE CUBIC 
FOOT OF CERTAIN GASES, TOGETHER WITH THE VOLUME OF 
THE PRODUCTS OF COMBUSTION. 



Name. 


Formula. 


Volume of 
Oxygen. 


Volume* 
of Air. 


Volume of 
Steam. 


Volume of 
Carbon 
Dioxide. 


Hydrogen 

Carbonic oxide. 

Methane 

Ethane 

Propane 

Butane 

Pentane 

Hexane 

Ethylenef 

Propylene:): .... 
Benzene§ 


H 2 

CO 

CH 4 

C 2 H 6 

C3H8 

C4H10 

C5H12 

C«Hi4 

C2H4 

C3H6 

CeHe 


0.5 
0.5 
2.0 

3-5 
5-o 

6.5 
8.0 

9-5 
3-o 
4-5 

7-5 


2-39 
2.39 

9-56 
16.73 
23.90 

31-07 
38.24 

45-41 
14-34 
21.51 

35-85 


I 
O 
2 

3 
4 
5 
6 

7 
2 

3 
3 


O 
I 
I 
2 

3 
4 
5 
6 
2 

3 
6 



* Air being 20.92 per cent by volume, 4.78 volumes contain 
I volume of oxygen. 
f The chief constituent of " illuminants," new name " ethene." 
% New name " propene." 
§ Often called benzol, not to be confounded with benzzne. 



102 



APPENDIX. 



TABLE IV. 

CALORIFIC POWER OF VARIOUS GASES* IN BRITISH THERMAL UNITS 

PER CUBIC FOOT. 



Name. 



Hydrogen 

Carbonic oxide 

Methane ■ 

Illuminantsf. . . 

Ethane 

Propane 

Butane. « 

Pentane 

Hexanef 

Ethylene 

Propylene 

Benzene 



Symbol. 



H 

CO 

CH 4 

C2H6 
C3H8 
C4H10 

CsHl2 

CeHi4 
C2H4 
C3H6 
CeHe 



6o° initial. 
328 final.§ 



263.2 

306.9 

853.O 

1700.O 



32 initial. 
32 final. 



345-4 
341.2 
1065.0 
2000.0 
1861.0 
2657.0 
3441.0 
4255.0 
5017.0 
1674.0 
2509.0 
4012.0 



* H. L. Payne, loc. cit. 

f Where the " illuminants " are derived chiefly from the decom- 
position of mineral oil. . 

% The chief constituent of the "gasolene" used in the gas 
machines for carburetting air. 

§ The temperature of steam at 100 lbs. absolute pressure. 

TABLE V. 

SHOWING THE WEIGHT OF A LITER AND SPECIFIC GRAVITY REFERRED 
TO AIR, OF CERTAIN GASES AT 0° C. AND 760 MM. 



Name of Gas. 



Carbonic oxide 
Carbon dioxide 

Hydrogen 

Methane 

Nitrogen 

Oxygen 

Air 



Weight, Grams. 


Spec 


ific Gravity. 


1. 251 




O.967 


I.966 




I- 519 


O.0896 




O.069 


0.7I5 




0.553 


1-255 




O.970 


1.430 




1. 105 


1.294 . 




I. OOO 



TABLES. 
TABLE VI. 



103 



SOLUBILITY OF VARIOUS GASES IN WATER. 

One volume of water at 20 C. absorbs the following volumes of 
gas reduced to o° C. and 760 mm. pressure. 



Name of Gas. 



Carbonic oxide 
Carbon dioxide 

Hydrogen 

Methane 

Nitrogen 

Oxygen 

Air 



Symbol. 


Volumes. 


CO 


O.023 


co 2 


O.901 


H 2 


0.019 


CH 4 


O.035 


N 2 


0.014 


o 2 


O.028 


.... 


O.O17 



MELTING-POINTS OF 



TABLE VII. 

VARIOUS METALS AND SALTS, FOR 
APPARATUS FIG. II. 



USE WITH 



Alphabetically. 

Aluminium 66o° C* 

Antimony 432 

f Barium chloride 922 

Bismuth 268 

Calcium fluoride 902 

Cadmium 320 

f Cadmium chloride.. . 541 

Copper 1095 

Lead.. ' 334 

f Potassium bromide. . 722 

f Potassium chloride. . 800 

f Sodium bromide 758 

fSodium carbonate. . . 849 

Tin 233 

Zinc — 433 



By Temperatures. 

Tin 233° C. 

Bismuth 268J 

Cadmium 320}: 

Lead 334$ 

Antimony 432^ 

Zinc 433$ 

Cadmium chloride. . . 541 J 

Aluminium 660* 

Potassium bromide. . 722§ 

Sodium bromide. . . . , 758§ 

Potassium chloride. . 8oo§ 

Sodium carbonate. . . 849§ 

Calcium fluoride .... 902§ 

Barium chloride 922§ 

Copper 1095* 



* Holman, Proc. Am. Academy, 31, 218 (1896). 
f These salts must be dried at 105 C. to a constant weight. 
X Carnelley, Meltijig- and Boiling-point Tables. 
§ Meyer, Riddle and Lamb, Ber. d. deut. Chem. Gesellsch., 27, 
3140 (1894). 



ro4 



APPENDIX. 
TABLE VIII. 



GIVING THE NUMBER OF TIMES THE THEORETICAL QUANTITY OF 
AIR SUPPLIED, WITH VARIOUS GAS ANALYSES.* 



c c°6 + 


N = 79- 


N = 8o. 


N = 81. 


N = 82. 


C0 2 +0+CO=2i 


C0 2 -j-0+CO=2o. 


C0 2 +0+CO=i9. 


C0 2 -fO+CO = i8. 


21 


1. 00 








20 


1.05 


1. 00 


.... 


.... 


19 


1. 10 


1.05 


I. OO 


.... 


18 


1. 17 


1. 10 


1.05 


I. OO 


17 


1.23 


1. 16 


I. IO 


1.05 


16 


I-3I 


1.23 


1. 16 


I. IO 


15 


I.40 


I-3I 


I.23 


1. 16 


14 


I.50 


1-39 


I.30 


1.22 


13 


1. 61 


1.49 


1-39 


1-30 


12 


1-75 


1.60 


1.48 


1.38 


II 


1. 91 


i-73 


1-59 


I.47 


IO 


2.10 


1.89 


1.72 


1.58 


9 


2.33 


2.07 


1.87 


I.70 


8 


2.62 


2.29 


2.04 


I.85 


7 


3.00 


2.57 


2.26 


2.02 


6 


3-50 


2.92 


2.52 


2.23 


5 


4.20 


3-39 


2.86 


2.48 


4 


5.25 


4.05 


3-30 


2.79 


3 


7.00 


5.00 


3-89 


3.20 


2 


10.50 


6.53 


4.76 


3-76 


1 


21 .00 


9-43 


6.10 


4-54 



* Coxe, Proc. N. E. Cotton Manufacturers' Assoc, 1895, 



TABLE IX. 

COMPARISON OF METRIC AND ENGLISH SYSTEMS, 

I cubic inch = 16.39 c.c. 

1 cubic foot = 28.315 liters. 

I Imperial gallon = 4-543 " 



I lb. avoirdupois = 453-593 grams. 

1 calorie = 3.969 B.T.U. (Rontgen). 



INDEX. 



PAGE 

Acid, hydrochloric, reagent 49 

Air-pumps, Bunsen's 8 

, Richards' 8 

, steam 9 

Anthracite coal, analysis of 61 

Aqueous vapor, table of tension of 100 

, specific heat 30 

Aspirator 9 

, Muencke's 54 

Bagasse, calorific power 63 

Benzophenon, boiling-point 26 

Berthier's method of determining calorific power of coal 88 

Bituminous coal, analysis of 59 

, varieties 60 

Blast-furnace gas, analysis of 65 

Boiling-point of various substances 26 

Brown coal 59 

, analysis of 59 

Bunte's gas apparatus 16 

method for determining quantity of heat passing up chim- 
ney 32, 33 

Calculations 28 

Calorimeters of Barrus 74 

Fischer 74 

Hempel 75 

Mahler 75 

Parr 86 

Thompson, L 74 

Thomson, W 74 

i°5 



106 INDEX. 

PAGE 

Carbon dioxide, determination of 13, 18, 21, 39 

, specific heat 30 

Carbonic oxide, determination of 14, 19, 22, 40 

, loss due to formation of 34 

, specific heat 30 

Charcoal, analysis of 62 

, preparation 61 

Coal, air required for combustion 61 

, calorific power 61 

, formation of 58 

, method of analysis 67 

Coal-gas, analysis of • *66 

, calorific power 66 

, manufacture of 66 

Coke, analysis of. 63 

, determination of. 67 

, preparation 62 

Coke-ovens 62 

Coke-oven gas, calorific power 66 

Cooling correction in calorimetry 85 

Course in gas analysis 55 

Cuprous chloride acid, reagent 49 

, ammoniacal, reagent 50 

Elliott's gas apparatus 20 

Formulae, Bunte's, for calorific power of coal 89 

, Dulong's, for calorific power of coal 89 

, Goutal's, for calorific power of coal 90 

, Lunge's, for heat passing up chimney 34 

, for heat of combustion with Mahler bomb 84 

, Mahler's, for calorific power of coal 89 

, Noyes', for calculation of heat lost 34 

, Ratio of air used to that theoretically necessary 32 

Fuel, determination of calorific power 74, 91 

, loss due to unconsumed 34 

Fuels, method of analysis of : ash 72 

carbon 68 

coke and volatile matter 67 

hydrogen 68 

moisture 67 



INDEX. 



IO/ 



PAGE 



Fuels, method of analysis of : nitrogen 73 

oxygen 73 

sulphur 73 

Fuming sulphuric acid, reagent 49 

Gas-balance of Custodis 24 

calorimeter, Junkers' 91 

composimeter of Uehling 24 

Gas, determination of calorific power by calculation 95 

laboratory, arrangement of 53 

Generator gas, see Producer-gas. 

Hempel's gas apparatus 35H-8 

Hydrocarbons, determination of 14, 23, 40 

Hydrogen, determination of 40, 45 

, reagent , 51 

" Illuminants, " calorific power of 102 

determination of 40 

Illuminating-gas, manufacture 66 

, Boston, analysis of. 96 

, method of analysis of 39 

, calorific power (calculated) , . 99 

Iron tubes, action of uncooled gases upon 2 

Junkers' gas-calorimeter 91 

Laboratory, arrangement of 55 

Lead, quantity reduced, a measure of the calorific power 88 

Lignite . 59 

Mahler bomb 75 

Melting-point boxes 27 

Melting-point of various substances 103 

Mercury, reagent 51 

Methane, determination of 40, 46 

Moisture in coal, determination of 67 

Naphthalene, boiling-point 26 

, calorific power 83 

Natural gas, analysis of 64 

, calorific power 66 



108 INDEX. 

PAGE 

Nitrogen, determination of, in coal 73 

, in gases 14, 46 

, specific heat 30 

Orsat's gas apparatus II 

Otto-Hoffman coke-ovens 62 

Oxygen, determination of, in air 38, 39 



in coal 



73 



, m gases 14, 19, 22, 40 

, specific heat 30 

Palladous chloride, reagent 52 

Peat, analysis of 58 

. briquettes 57 

, calorific power 58 

, formation 57 

, moisture in 57 

Petroleum, formation of 63 

Petroleum, calorific power 63 

, crude, analysis of. 63 

Phosphorus, reagent 52 

Potassium hydrate, reagent 52 

pyrogallate, reagent 52 

1 ' Pounds of air per pound of coal " 28 

Producer- gas, analysis of 65 

, calorific power 66 

Pyrometer, Le Chatelier's thermoelectric 26 

Quantity of heat passing up chimney 29, 32 

Ratio of air used to that theoretically necessary 32 

Sampling apparatus „ 3, 6 

gases, method of 2 

, tubes for 2 

solid fuels, method of 67 

Semet-Solvay coke-ovens 62 

Semi-bituminous coal, analysis of 60 

Sodium hydrate, reagent 53 

pyrogallate, reagent 53 

Specific heat of various gases 30 

Spent tan-bark, calorific power 63 



INDEX. 109 

PAGK 

Sulphur, boiling-point 26 

Sulphuric acid, fuming, reagent 49 

Table of quantity of air necessary to burn gases 10 1 

tension of aqueous vapor 100 

weight of aqueous vapor in air 100 

calorific power of gases 102 

solubility of gases 103 

specific gravity of gases 102 

volumetric specific heats of gases 100 

weights of gases 102 

melting-points of metals and salts 103 

metric and English systems 104 

theoretical quantity of air supplied 104 

Temperature, measurement of. 25 

Thermometers 25 

, testing of 26 

Tubes for sampling 2 

Volatile matter, determination of 67 

Water-gas, analysis of 66 

, calorific power 66 

Wheat- straw, calorific power 63 

Wood, analysis of. 57 

, calorific power 57 

, moisture in 56, 57 



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Adriance's Laboratory Calculations and Specific Gravity Tables i2mo, 

Alexeyeff's General Principles of Organic Synthesis. (Matthews.) 8vo, 

Allen's Tables for Iron Analysis 8vo, 

Arnold's Compendium of Chemistry. (Mandel.) Small 8vo, 

Austen's Notes for Chemical Students nmo, 

Bernadou's Smokeless Powder. — Nitro-cellulose, and Theory of the Cellulose 
Molecule i2mo, 

* Browning's Introduction to the Rarer Elements 8vo, 

Brush and Penfield's Manual of Determinative Mineralogy 8vo, 

Claassen's Beet-sugar Manufacture. (Hall and Rolfe.) 8vo, 

Classen's Quantitative Chemical Analysis by Electrolysis. (Boltwood.). .8vo, 
Cohn's Indicators and Test-papers i2mo, 

Tests and Reagents 8vo, 

Crafts's Short Course in Qualitative Chemical Analysis. (Schaeffer.). . . nmo, 
Dolezalek's Theory of the Lead Accumulator (Storage Battery). (Von 

Ende.) i2mo, 

Drechsel's Chemical Reactions. (Merrill.) i2mo, 

Duhem's Thermodynamics and Chemistry. (Burgess.) 8vo, 

Eissler's Modern High Explosives 8vo, 

Effront's Enzymes and their Applications. (Prescott.) 8vo, 

Erdmann's Introduction to Chemical Preparations. (Dunlap.) i2mo, 

Fletcher's Practical Instructions in Quantitative Assaying with the Blowpipe. 

i2mo, morocco, 

Fowler's Sewage Works Analyses i2mo. 

Fresenius's Manual of Qualitative Chemical Analysis. (Wells.) 8vo, 

Manual of Qualitative Chemical Analysis. Part I. Descriptive. (Wells.) 8vo, 
System of Instruction in Quantitative Chemical Analysis. (Cohn.) 

2 vols 8vo, 

Fuertes's Water and Public Health i2mo, 

Furman's Manual of Practical Assaying 8vo, 

* Getman's Exercises in Physical Chemistry i2mo, 

Gill's Gas and Fuel Analysis for Engineers i2mo, 

Grotenfelt's Principles of Modern Dairy Practice. (Woll.) nmo, 

Groth's Introduction to Chemical Crystallography (Marshall) i2mo, 

Hammarsten's Text-book of Physiological Chemistry. (Mandel.) 8vo, 

Helm's Principles of Mathematical Chemistry. (Morgan.) i2mo, 

Hering's Ready Reference Tables (Conversion Factors) i6mo, morocco, 

Hind's Inorganic Chemistry 8vo, 

* Laboratory Manual for Students i2mo, 

Holleman's Text-book of Inorganic Chemistry. (Cooper.) 8vo, 

Text-book of Organic Chemistry. (Walker and Mott.) 8vo, 

* Laboratory Manual of Organic Chemistry. (Walker.) i2mo, 

Hopkins's Oil-chemists' Handbook 8vo, 

Jackson's Directions for Laboratory Work in Physiological Chemistry. .8vo, 

Keep's Cast Iron 8vo, 

Ladd's Manual of Quantitative Chemical Analysis i2mo, 

Landauer's Spectrum Analysis. (Tingle.) 8vo, 

* Langworthy and Austen. The Occurrence of Aluminium in Vegetable 

Products, Animal Products, and Natural Waters 8vo, 

Lassar-Cohn's Practical Urinary Analysis. (Lorenz.) i2mo, 

Application of Some General Reactions to Investigations in Organic 

Chemistry. (Tingle.) i2mo, i oo 

Leach's The Inspection and Analysis of Food with Special Reference to State 

Control 8vo, 7 50 

Lob's Electrochemistry of Organic Compounds. (Lorenz.) 8vo, 3 00 

Lodge's Notes on Assaying and Metallurgical Laboratory Experiments. .. .8vo, 3 00 

Low's Technical Method of Ore Analysis 8vo 3 00 

Lunge's Techno-chemical Analysis. (Cohn.) 1 21110 1 00 

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* McKay and Larsen's Principles and Practice' of Butter-making 8vo 

Mandel's Handbook for Bio-chemical Laboratory i2mo, 

* Martin's Laboratory Guide to Qualitative Analysis with the Blowpipe . . i2mo, 
Mason's Water-supply. (Considered Principally from a Sanitary Standpoint.) 

3d Edition, Rewritten 8vo s 

Examination of Water. (Chemical and Bacteriological.) nmo, 

Matthew's The Textile Fibres 8vo, 

Meyer's Determination of Radicles in Carbon Compounds. (Tingle.), .nmo, 

Miller's Manual of Assaying i2mo, 

Cyanide Process nmo, 

Minet's Production of Aluminum and its Industrial Use. (Waldo.) . . . . i2mo, 

Mixter's Elementary Text-book of Chemistry i2mo, 

Morgan's An Outline of the Theory of Solutions and its Results i2mo, 

Elements of Physical Chemistry i2mo, 

* Physical, Chemistry for Electrical Engineers, , i2mo, 

Morse's Calculations used in Cane-sugar Factories i6mo, morocco, 

Mulliken's General Method for the Identification of Pure Organic Compounds. 

Vol. I Large 8vo, 

O'Brine's Laboratory Guide in Chemical Analysis 8vo, 

O'Driscoll's Notes on the Treatment of Gold Ores 8vo, 

Ostwald's Conversations on Chemistry. Part One. (Ramsey.). ..... .i2mo, 

Part Two. (Turnbull.) i2mo, 

* Penfield's Notes on Determinative Mineralogy and Record of Mineral Tests. 

8vo, paper, 

Pictet's The Alkaloids and their Chemical Constitution. (Biddle.) 8vo, 

Pinner's Introduction to Organic Chemistry. (Austen.) i2mo : 

Poole's Calorific Power of Fuels 8vo, 

Prescott and Winslow's Elements of Water Bacteriology, with Special Refer- 
ence to Sanitary Water Analysis i2mo, 

* Reisig's Guide to Piece-dyeing Svo, 

Richards and Woodman's Air,Water, and Food from a Sanitary Standpoint. ,8vo, 
Ricketts and Russell's Skeleton Notes upon Inorganic Chemistry. (Part I. 

Non-metallic Elements.) 8vo, morocco, 

Ricketts and Miller's Notes on Assaying 8vo, 

Rideal's Sewage and the Bacterial Purification of Sewage Svo, 

Disinfection and the Preservation of Food Svo, 

Riggs's Elementary Manual for the Chemical Laboratory 8vo, 

Robine and Lenglen's Cyanide Industry. (Le Clerc.) 8vo, 

Rostoski's Serum Diagnosis. (Bolduan.) i2mo, 

Ruddiman's Incompatibilities in Prescriptions Svo, 

* Whys in Pharmacy , i2mo, 

Sabin's Industrial and Artistic Technology of Paints and Varnish 8vo, 

Salkowski's Physiological and Pathological Chemistry. (Orndorff.) 8vo, 

Schimpf's Text-book of Volumetric Analysis. c i2mo, 

Essentials of Volumetric Analysis i2mo, 

* Qualitative Chemical Analysis . .8vo, 

Smith's Lecture Notes on Chemistry for Dental Students „ . .8vo, 

Spencer's Handbook for Chemists of Beet-sugar Houses i6mo, morocco. 

Handbook for Cane Sugar Manufacturers i6mo, morocco, 

Stockbridge's Rocks and Soils 8vo, 

* Tillman's Elementary Lessons in Heat 8vo, 

* Descriptive General Chemistry 8vo, 

Treadwell's Qualitative Analysis. (Hall.) 8vo, 

Quantitative Analysis. (Hall.) 8vo, 

Turneaure and Russell's Public Water-supplies 8vo, 

Van Deventer's Physical Chemistry for Beginners. (Boltwood.) i2mo, 

* Walke's Lectures on Explosives .• 8vo, 

Ware's Beet-sugar Manufacture and Refining . .Small 8vo, cloth, 

Washington's Manual of the Chemical Analysis of Rocks 8vo, 

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-4 OO 
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"Wassermann's Immune Sera : Hemolysins, Cytotoxins, and Precipitins. (Bol- 

duan -) nmo, t 00 

^Weaver's Military Explosives gvo, 3 00 

Wehrenfennig's Analysis and Softening of Boiler Feed- Water 8vo. 

Wells's Laboratory Guide in Qualitative Chemical Analysis 8vo, 

Short Course in Inorganic Qualitative Chemical Analysis for Engineering 

Students i2mo, 1 50 

Text-book of Chemical Arithmetic I2mo , 1 25 

Whipple's Microscopy of Drinking-water 8vo, 3 50 

Wilson's Cyanide Processes i2mo, 1 50 

Chlorination Process i2mo, 1 50 

Winton's Microscopy of Vegetable Foods 8vo, 7 50 

Wulling's Elementary Course in Inorganic, Pharmaceutical, and Medical 

Chemistry, I2mo> 2 00 



CIVIL ENGINEERING. 

BRIDGES AND ROOFS, HYDRAULICS. MATERIALS OF ENGINEERING. 

RAILWAY ENGINEERING. 

Baker's Engineers' Surveying Instruments i2mo, 

Bixby's Graphical Computing Table Paper ig£ <24i inches. 

*** Burr's Ancient and Modern Engineering and the Isthmian Cana ... (Postage, 

27 cents additional.) 8vo, 

Comstock's Field Astronomy for Engineers 8vo, 

Davis's Elevation and Stadia Tables 8vo, 

^Elliott's Engineering for Land Drainage i2mo, 

Practical Farm Drainage i2mo, 

^Fiebeger's Treatise on Civil Engineering 8vo, 

Flemer's Phototopographic Methods and Instruments 8vo, 

Polwell's Sewerage. (Designing and Maintenance.) 8vo, 

'.Freitag's Architectural Engineering. 2d Edition, Rewritten 8vo, 

French and Ives's Stereotomy 8vo, 

Goodhue's Municipal Improvements i2mo, 

"Goodrich's Economic Disposal of Towns' Refuse , 8vo, 

Oore's Elements of Geodesy 8vo, 

"Hayford's Text-book of Geodetic Astronomy 8vo, 

.Hering's Ready Reference Tables (Conversion Factors) i6mo, morocco, 

Howe's Retaining Walls tor Earth i2mo, 

* Ives's Adjustments of the Engineer's Transit and Level i6mo, Bds. 

Ives and Hilts's Problems in Surveying i6mo, morocco, 

Johnson's (J. B.) Theory and Practice of Surveying Small 8vo, 

Johnson's (L. J.) Statics by Algebraic and Graphic Methods 8vo, 

Laplace's Philosophical Essay on Probabilities. (Truscott and Emory.) . nmo, 
IMahan's Treatise on Civil Engineering. (1873.) (Wood.) 8vo, 

* Descriptive Geometry 8vo, 

.Merriman's Elements of Precise Surveying and Geodesy 8vo, 

'Merriman and Brooks's Handbook for Surveyors i6mo, morocco, 

.Nugent's Plane Surveying 8vo, 

fOgden's Sewer Design nmo, 

Parsons's Disposal of Municipal Refuse 8vo, 

Patton's Treatise on Civil Engineering 8vo half leather, 

Reed's Topographical Drawing and Sketching 4to, 

Rtdeal's Sewage and the Bacterial Purification of Sewage 8vo, 

Siebert and Biggin's Modern Stone-cutting and Masonry 8vo, 

Smith's Manual of Topographical Drawing. (McMillan. ^ 8vo, 

Sondericker's Graphic Statics, with Applications to Trusses, Beams, and Arches. 

8vo, 2 00 

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Taylor and Thompson's Treatise on Concrete, Plain and Reinforced 8vo, 

* Trautwine's Civil Engineer's Pocket-book i6mo, morocco, 

Venable's Garbage Crematories in America 8vo, 

Wait's Engineering and Architectural Jurisprudence 8vo, 

Sheep, 
Law of Operations Preliminary to Construction in Engineering and Archi- 
tecture , 8vo, 

Sheep, 

Law of Contracts 8vo, 

Warren's Stereotomy — Problems in Stone-cutting 8vo, 

Webb's Problems in the Use and Adjustment of Engineering Instruments. 

i6mo, morocco, 
Wilson's Topographic Surveying 8vo, 



BRIDGES AND ROOFS. 

Boiler's Practical Treatise on the Construction of Iron Highway Bridges. .8vo, 

* Thames River Bridge 4to, paper, 

Burr's Course on the Stresses in Bridges and Roof Trusses, Arched Ribs, and 

Suspension Bridges 8vo, 

Burr and Falk's Influence Lines for Bridge and Roof Computations 8vo, 

Design and Construction of Metallic Bridges 8VO, 

Du Bois's Mechanics of Engineering. Vol. II £mall 4to/ 

Foster's Treatise on Wooden Trestle Bridges 4to, 

Fowler's Ordinary Foundations 8vo, 

Greene's Roof Trusses 8vo, 

Bridge Trusses 8vo, 

Arches in Wood, Iron, and Stone 8vo ? 

Howe's Treatise on Arches 8vo, 

Design of Simple Roof-trusses in Wood and Steel 8vo, 

Symmetrical Masonry Arches 8vo, 

Johnson, Bryan, and Turneaure's Theory and Practice in the Designing of 

Modern Framed Structures Small 4to, 10 oo> 

Merrlman and Jacoby's Text-book on Roofs and Bridges : 

Part I, Stresses in Simple Trusses 8vo, 

Part II. Graphic Statics 8vo, 

Part III. Bridge Design 8vo, 

Part IV. Higher Structures 8vo, 

Morison's Memphis Bridge 4*0, 

Waddell's De Pontibus, a Pocket-book for Bridge Engineers. . i6no, morocco, 

* Specifications for Steel Bridges i2mo, 

Wright's Designing of Draw-spans. Two parts in one volume 8vo, 



HYDRAULICS. 

Barnes's Ice Formation 8vo, 3 oc> 

Bazin's Experiments upon the Contraction of the Liquid Vein Issuing from 

an Orifice. (Trautwine.) 8vo, 

Bovey's Treatise on Hydraulics 8vo, 

Church's Mechanics of Engineering 8vo, 

Diagrams of Mean Velocity of Water in Open Channels paper, 

Hydraulic Motors. 8vo * 

Coffin's Graphical Solution of Hydraulic Problems i6mo, morocco, 

Flather's Dynamometers, and the Measurement of Power i2mo, 

Folwell's Water-supply Engineering. 8vo, 

Frizell's Water-power Svo,- 

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Fuertes's Water and Public Health , . i2ino, i 50 

Water-filtration Works i2mo, 2 50 

Ganguillet and Kutter's General Formula for the Uniform Flow of Water in 

Rivers and Other Channels. (Hering and Trautwine.) 8vo, 4 00 

Hazen's Filtration of Public Water-supply 8vo, 3 00 

Hazlehurst's Tov/ers and Tanks for Water- works 8vo, 2 50 

Herschel's 115 Experiments on the Carrying Capacity of Large, Riveted, Metal 

Conduits 8vo, 2 00 

Mason's Water-supply. (Considered Principally from a Sanitary Standpoint.) 

8vo> 

Merriman's Treatise on Hydraulics 8vo, 

■* Michie's Elements of Analytical Mechanics 8vo, 

Schuyler's Reservoirs for Irrigation, Water-power, and Domestic Water- 
supply Large 8vo, 

** Thomas and Watt's Improvement of Rivers (Post., 44c. additional.) 4to, 

Turneaure and Russell's Public Water-supplies 8vo, 

Wegmann's Design and Construction of Dams 4to, 

Water-supply of the City of New York from 1658 to 1895 4to, 

Williams and Hazen's Hydraulic Tables 8vo, 

Wilson's Irrigation Engineering Small 8vo, 

Wolff's Windmill as a Prime Mover 8vo, 

Wood's Turbines 8vo, 

Elements of Analytical Mechanics 8vo, 



MATERIALS OF ENGINEERING. 

Baker's Treatise on Masonry Construction 8vo, 

Roads and Pavements 8vo, 

Black's United States Public Works Oblong 4to, 

* Bovey's Strength of Materials and Theory of Structures 8vo, 

Burr's Elasticity and Resistance of the Materials of Engineering 8vo, 

Byrne's Highway Construction 8vo, 

Inspection of the Materials and Workmanship Employed in Construction. 

i6mo, 

Church's Mechanics of Engineering 8vo, 

Du Bois's Mechanics of Engineering. Vol. I Small 4to, 

^Eckel's Cements, Limes, and Plasters 8vo, 

Johnson's Materials of Construction Large 8vo, 

Fowler's Ordinary Foundations. . 8vo, 

Graves's Forest Mensuration 8vo, 

* Greene's Structural Mechanics 8vo, 

Keep's Cast Iron 8vo, 

Lanza's Applied Mechanics 8vo, 

Marten's Handbook on Testing Materials. (Henning.) 2 vols 8vo, 

Maurer's Technical Mechanics 8vo, 

Merrill's Stones for Building and Decoration 8vo, 

Merriman's Mechanics of Materials 8vo, 

Strength of Materials i2mo, 

Metcalf's Steel. A Manual for Steel-users i2mo, 

Patton's Practical Treatise on Foundations 8vo, 

Richardson's Modern Asphalt Pavements 8vo, 

Richey's Handbook for Superintendents of Construction i6mo, mor., 

* Ries's Clays: Their Occurrence, Properties, and Uses 8vo, 

Rockwell's Roads and Pavements in France 12010, 

Sabin's Industrial and Artistic Technology of Paints and Varnish 8vo, 

Smith's Materials of Machines nmo, 

Snow's Principal Species of Wood 8vo, 

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Spalding's Hydraulic Cement i2mo, 2 00 

Text-book on Roads and Pavements i2mo, 2 00 

Taylor and Thompson's Treatise on Concrete. Plain and Reinforced 8vo, 5 00 

Thurston's Materials of Engineering. 3 Parts 8vo, 8 00 

Part I. Non-metallic Materials of Engineering and Metallurgy 8vo, 2 00 

Part II Iron and Steel 8vo, 3 50 

Part III. A Treatise on Brasses, Bronzes, and Other Alloys and their 

Constituents. . .. 8vo, 2 50 

Thurston's Text-book of the Materials of Construction 8vo, 5 00 

Tillson's Street Pavements and Paving Materials 8vo, 4 00 

Waddell's De Pontibus (A Pocket-book for Bridge Engineers.). . i6mo, mor., 2 00 

Specifications for Steel Bridges. i2mo, 1 25 

Wood's (De V.) Treatise on the Resistance of Materials, and an Appendix on 

the Preservation of Timber. . 8vo, 2 00 

Wood's (De V.) Elements of Analytical Mechanics 8vo, 3 00 

Wood's (M. P.) Rustless Coatings: Corrosion and Electrolysis of Iron and 

Steel 8vo, 4 00 



RAILWAY ENGINEERING. 

Andrew's Handbook for Street Railway Engineers 3x5 inches, morocco, 1 25 

Berg's Buildings and Structures of American Railroads 4to, 5 00 

Brook's Handbook of Street Railroad Location i6mo, morocco. 1 50 

Butt's Civil Engineer's Field-book i6mo, morocco, 2 50 

Crandall's Transition Curve i6mo, morocco, 1 50 

Railway and Other Earthwork Tables .8vo s 1 50 

Dawson's "Engineering" and Electric Traction Pocket-book . i6mo. morccco, 5 00 

Dredge's History of the Pennsylvania Railroad: (1879) Paper, 5 00 

* Drinker's Tunnelling, Explosive Compounds, and Rock Drills. 4to, half mor., 25 00 

Fisher's Table of Cubic Yards Cardboard, 25 

Godwin's Railroad Engineers' Field-book and Explorers' Guide. . . i6mo, mor., 2 50 

Howard's Transition Curve Field-book i6mo, morocco, 1 50 

Hudson's Tables for Calculating the Cubic Contents of Excavations and Em- 
bankments. 8vo, 1 00 

Molitor and Beard's Manual for Resident Engineers. = i6mo, 1 co 

Nagles Field Manual for Railroad Engineers i6mo, morocco » 3 co 

Philbrick's Field Manual for Engineers. . , i6mo, morocco, 3 00 

Searles's Field Engineering i6mo, morocco, 3 00 

Railroad Spiral i6mo, morocco, 1 50 

Taylor's Prismoidal Formulas and Earthwork. . , • 8vo, 1 50 

* Trautwine v s Method of Calculating the Cube Contents of Excavations and 

Embankments by the Aid of Diagrams 8vo, 2 00 

The Field Practice of Laying Out Circular Curves for Railroads. 

i2mo, morocco, 2 50 

Cross-section Sheet Paper, 25 

Webb's Railroad Construction i6mo, morocco, 5 00 

Economics of Railroad Construction Large i2mo, 2 50 

Wellington's Economic Theory of the Location of Railways. Small 8vo. 5 00 



DRAWING. 

Barr's Kinematics of Machinery 8vo 2 50 

* Bartlett's Mechanical Drawing 8vo, 3 00 

* " " ". Abridged Ed . 8vo, 150 

Coolidge's Manual of Drawing . . . 8vo, paper, 1 00 

9 



Coolidge and Freeman's Elements of General Drafting for Mechanical Engi- 
neers Oblong 4to, 

Durley's Kinematics of Machines 8vo, 

Emch's Introduction to Projective Geometry and its Applications 8vo, 

Hill's Text-book on Shades and Shadows, and Perspective 8vo, 

Jamison's Elements of Mechanical Drawing 8vo, 

Advanced Mechanical Drawing 8vo, 

Jones's Machine Design: 

Part I. Kinematics of Machinery 8vo, 

Part II. Form, Strength, and Proportions of Parts 8vo, 

MacCord's Elements of Descriptive Geometry . .8vo, 

Kinematics; or, Practical Mechanism 8vo, 

Mechanical Drawing 4to, 

Velocity Diagrams 8vo, 

MacLeod's Descriptive Geometry Small 8vo, 

* Mahan's Descriptive Geometry and Stone-cutting 8vo, 

Industrial Drawing. (Thompson.) 8vo, 

Moyer's Descriptive Geometry 8vo, 

Reed's Topographical Drawing and Sketching 4to, 

Reid's Course in Mechanical Drawing 8vo, 

Text-book of Mechanical Drawing and Elementary Machine Design. 8vo, 

Robinson's Principles of Mechanism 8vo, 

Schwamb and Merrill's Elements of Mechanism 8vo, 

Smith's (R. S.) Manual of Topographical Drawing. (McMillan.). 8vo, 

Smith (A. W.) and Marx's l T achine Design 8vo, 

* Titsworth's Elements of Mechanical Drawing Oblong 8vo, 

Warren's Elements of Plane and Solid Free-hand Geometrical Drawing. i2mo, 

Drafting Instruments and Operations i2mo, 

Manual of Elementary Projection Drawing i2mo, 

Manual of Elementary Problems in the Linear Perspective of Form and 

Shadow i2mo, 

Plane Problems in Elementary Geometry i2mo, 

Primary Geometry i2mo, 

Elements of Descriptive Geometry, Shadows, and Perspective 8vo, 

General Problems of Shades and Shadows 8vo, 

Elements of Machine Construction and Drawing 8vo, 

Problems, Theorems, and Examples in Descriptive Geometry. ..... .8vo, 

Weisbach's Kinematics and Power of Transmission. (Hermann and 

Klein.) 8vo, 

Whelpley's Practical Instruction in the Art of Letter Engraving 12 mo, 

Wilson's (H. M.) Topographic Surveying 8vo, 

Wilson's (V. T.) Free-hand Perspective 8vo, 

Wilson's (V. T.) Frae-hand Lettering .' 8vo, 

Woolf's Elementary Course in Descriptive Geometry Large 8vo, 



ELECTRICITY AND PHYSICS. 

Anthony and Brackett's Text-book of Physics. (Magie.) Small 8vo, 

Anthony's Lecture-notes on the Theory of Electrical Measurements. . . . nmo, 

Benjamin's History of Electricity 8vo, 

Voltaic Cell 8vo, 

Classen's Quantitative Chemical Analysis by Electrolysis. (Boltwood.).8vo, 

* Collins's Manual of Wireless Telegraphy i2mo, 

Morocco, 

Crehore and Squier's Polarizing Photo-chronograph. . 8vo, 

Dawson's "Engineering" and Electric Traction Pocket-book. i6mo, morocco, 

10 



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Dolezalek's Theory of the Lead Accumulator (Storage Battery). (Von 

Ende.) '. i2mo, 

Duhem's Thermodynamics and Chemistry. (Burgess.) 8vo, 

Flather's Dynamometers, and the Measurement of Power i2mo, 

Gilbert's De Magnete. (Mottelay.) 8vo, 

Hanchett's Alternating Currents Explained i2mo, 

Hering's Ready Reference Tables (Conversion Factors) i6mo, morocco, 

Holman's Precision of Measurements 8vo, 

Telescopic Mirror-scale Method, Adjustments, and Tests. . . .Large 8vo, 

Kinzbrunner's Testing of Continuous-current Machines 8vo, 

Landauer's Spectrum Analysis. (Tingle.) 8vo, 

Le Chatelier s High-temperature Measurements. (Boudouard — Burgess.) i2mo, 
Lob's Electrochemistry of Organic Compounds. (Lorenz.) 8vo, 

* Lyons'? Treatise on Electromagnetic Phenomena. Vols. I. and II. 8vo, each, 

* Michie's Elements of Wave Motion Relating to Sound and Light 8vo, 

Niaudet's Elementary Treatise on Electric Batteries. (Fishback.) i2mo, 

* Parshall and Hobart's Electric Machine Design 4to, half morocco, 

* Rosenberg's Electrical Engineering. (Haldane Gee — Kinzbrunner.). . .8vo, 

Ryan, Norris, and Hoxie's Electrical Machinery. Vol. 1 8vo, 

Thurston's Stationary Steam-engines 8vo, 

* Tillman's Elementary Lessons in Heat 8vo, 

Tory and Pitcher's Manual of Laboratory Physics, c Small 8vo, 

Ulke's Modern Electrolytic Copper Refining 8vo, 



LAW. 

* Davis's Elements of Law 8vo, 

* Treatise on the Military Law of United States 8vo, 

* Sheep, 

Manual for Courts-martial „ i6mo, morocco, 

Wait's Engineering and Architectural Jurisprudence , 8vo, 

Sheep, 
Law of Operations Preliminary to Construction in Engineering and Archi- 
tecture 8vo 7 

Sheep, 

Law of Contracts 8vo, 

Winthrop's Abridgment of Military Law. . ; i2mo, 



MANUFACTURES. 

Bernadou's Smokeless Powder — Mtro-celluiose and Theory of the Cellulose 

Molecule i2mo, 

Bolland's Iron Founder i2mo, 

The Iron Founder," Supplement i2mo, 

Encyclopedia of Founding and Dictionary of Foundry Terms Used in the 

Practice of Moulding i2mo, 

Claassen's Beet-sugar Manufacture. (Hall and Rolfe.) 8vo, 

* Eckel's Cements, Limes, and Plasters 8vo, 

Eissler's Modern High Explosives 8vo, 

Effront's Enzymes and their Applications. (Prescott.) 8vo, 

Fitzgerald's Boston Machinist i2mo, 

Ford's Boiler Making for Boiler Makers i8mo, 

Hopkin's Oil-chemists' Handbook 8vo, 

Keep's Cast Iron , 8vo, 

11 



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Xeach's The Inspection and Analysis of Food with Special Reference to State 

Control Large 8vo, 7 50 

'* McKay and Larsen's Principles and Practice of Butter-making 8vo, 1 50 

Matthews's The Textile Fibres 8vo, 3 50 

Metcalf's Steel. A Manual for Steel-users i2mo, 2 00 

Metcalfe's Cost of Manufactures — And the Administration of Workshops. 8vo, 5 00 

Meyer's Modern Locomotive Construction 4to, 10 00 

Morse's Calculations used in Cane-sugar Factories i6mo, morocco, 1 50 

* Reisig's Guide to Piece-dyeing 8vo, 25 00 

Rice's Concrete-block Manufacture 8vo, 2 00 

Sabin's Industrial and Artistic Technology of Paints and Varnish 8vo, 3 00 

Smith's Press-working of Metals 8vo, 3 00 

Spalding's Hydraulic Cement i2mo, 2 00 

Spencer's Handbook for Chemists of Beet-sugar Houses i6mo, morocco, 3 00 

Handbook for Cane Sugar Manufacturers T6mo, morocco, 3 00 

Taylor and Thompson's Treatise on Concrete, Plain and Reinforced 8vo, 5 00 

Thurston's Manual of Steam-boilers, their Designs, Construction and Opera- 
tion 8vo, 5 00 

* Walke's Lectures on Explosives 8vo, 4 00 

Ware's Beet-sugar Manufacture and Refining Small 8vo, 4 00 

Weaver's Military Explosives 8vo, 3 00 

West's American Foundry Practice i2mo, 2 50 

Moulder's Text-book I i2mo, 2 50 

Wolff's" Windmill as a Prime Mover 8vo, 3 00 

Wood's Rustless Coatings: Corrosion and Electrolysis of Iron and Steel. .8vo, 4 00 



MATHEMATICS. 

Baker's Elliptic Functions 8vo, 

* Bass's Elements of Differential Calculus i2mo, 

Briggs's Elements of Plane Analytic Geometry i2mo, 

Compton's Manual of Logarithmic Computations i2mo, 

Davis's Introduction to the Logic of Algebra 8vo, 

* Dickson's College Algebra Large i2mo, 

* Introduction to the Theory of Algebraic Equations Large i2mo, 

Emch's Introduction to Projective Geometry and its Applications 8vo, 

Halsted's Elements of Geometry ' 8vo, 

Elementary Synthetic Geometry 8vo, 

Rational Geometry i2mo, 

* Johnson's (J. B.) Three-place Logarithmic Tables: Vest-pocket size. paper, 

100 copies for 

* Mounted on heavy cardboard, 8X10 inches, 

10 copies for 
Johnson's (W W.) Elementary Treatise on Differential Calculus. .Small 8vo, 

Elementary Treatise on the Integral Calculus Small 8vo, 

Johnsoa's (W. W.) Curve Tracing in Cartesian Co-ordinates i2mo, 

Johnson's (W W.) Treatise on Ordinary and Partial Differential Equations. 

Small 8vo, 
Johnson's (W, W.) Theory of Errors and the Method of Least Squares. i2mo, 

* Johnson's (W W.) Theoretical Mechanics . i2mo, 

Laplace's Philosophical Essay on Probabilities. (Truscott and Emory.) . i2mo, 

* Ludlow and Bass. Elements of Trigonometry and Logarithmic and Other 

Tables 8vo f 

Trigonometry and Tables published separately Each, 

* Ludlow's Logarithmic and Trigonometric Tables 8vo. 

Manning's Irrational Numbers and their Representation by Sequences and Series 

umo 1 25 
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Mathematical Monographs. Edited by Mansfield Merriman and Robert 

• S. Woodward Octavo, each i oo 

No. i. History of Modern Mathematics, by David Eugene Smith. 
No. 2. Synthetic Projective Geometry, by George Bruce Halsted. 
No. 3. Determinants, by Laenas Gifford Weld. No. 4. Hyper- 
bolic Functions, by James McMahon. No. 5. Harmonic Func- 
tions, by William E. Byerly. No c 6. Grassmann's Space Analysis, 
by Edward W c Hyde. No. 7. Probability and Theory of Errors, 
by Robert S. Woodward. No. 8. Vector Analysis and Quaternions, 
by Alexander Macfarlane. No. 9. Differential Equations, by 
William Woolsey Johnson. No. 10. The Solution of Equations, 
by Mansfield Merriman. No. 11. Functions of a Complex Variable, 
by Thomas S. Fiske. 

Maurer's Technical Mechanics. «... 8vo, 4 00 

Merriman i 's Method of Least Squares 8vo, 2 00 

Rice and Johnson's Elementary Treatise on the Differential Calculus. . Sm. 8vo, 3 00 

Differential and Integral Calculus. 2 vols, in one. Small 8vo, 2 50 

Wood's Elements of Co-ordinate Geometry. 8vo, 2 00 

Trigonometry: Analytical, Plane, and Spherical i2mo, 1 00 



MECHANICAL ENGINEERING. 

MATERIALS OF ENGINEERING, STEAM-ENGINES AND BOILERS. 

Bacon's Forge Practice , i2mo, 1 50 

Baldwin's Steam Heating for Buildings. i2mo, 2 50 

Barr's Kinematics of Machinery. ' 8vo, 2 50 

* Bartlett's Mechanical Drawing 8vo, 3 00 

Abridged Ed 8vo, 150 

Benjamin's Wrinkles and Recipes i2mo, 2 00 

Carpenter's Experimental Engineering 8vo, 6 00 

Heating and Ventilating Buildings 8vo, 4 00 

Cary's Smoke Suppression in Plants using Bituminous Coal. (In Prepara- 
tion.) 

Clerk's Gas and Oil Engine Small 8vo, 4 00 

Coolidge's Manual of Drawing 8vo, paper, 1 00 

Coolidge and Freeman's Elements of General Drafting for Mechanical En- 
gineers Oblong 4to, 2 50 

Cromwell's Treatise on Toothed Gearing i2mo, 1 50 

Treatise on Belts and Pulleys i2mo, 1 50 

Duriey's Kinematics of Machines 8vo, 4 00 

Fiather's Dynamometers and the Measurement of Power. i2mo, 3 00 

Rope Driving i2mo, 2 00 

Gill's Gas and Fuel Analysis for Engineers i2mo, 1 25 

Hall's Car Lubrication i2mo, 1 00 

Hering's Ready Reference Tables (Conversion Factors) i6mo, morocco, 2 50 

Hutton's The Gas Engine «, 8vo, 5 00 

Jamison's Mechanical Drawing 8vo, 2 50 

Jones's Machine Design: 

Part I. Kinematics of Machinery. . «, 8vo, 1 50 

Part II. Form, Strength, and Proportions of Parts 8vo, 3 00 

Kent's Mechanical Engineers' Pocket-book i6mo, morocco, 5 00 

Kerr's Power and Power Transmission 8vo, 2 00 

Leonard's Machine Shop, Tools, and Methods 8vo, 4 00 

* Lorenz's Modern Refrigerating Machinery. (Pope, Haven, and Dean.) . . 8vo, 4 00 
JMacCord's Kinematics; or Practical Mechanism 8vo, 5 00 

Mechanical Drawing 4to. 4 00 

Velocity Diagrams. , 8vo, 1 50 

13 



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MacFarland's Standard Reduction Factors for Gases 8vo, 

Mahan's Industrial Drawing. (Thompson. ). 8vo, 

Poole's Calorific Power of Fuels 8vo, 

Reid's Course in Mechanical Drawing 8vo» 

Text-book of Mechanical Drawing and Elementary Machine Design. 8vo, 

Richard's Compressed Air i2mo, 

Robinson's Principles of Mechanism 8vo, 

Schwamb and Merrill's Elements of Mechanism 8vo, 

Smith's (O.) Press-working of Metals 8vo, 

Smith (A. W.) and Marx's Machine Design 8vo, 

Thurston's Treatise on Friction and Lost Work in Machinery and Mill 
Work.. . „ 8vo, 

Animal as a Machine and Prime Motor, and the Laws of Energetics. i2mo, 

Warren's Elements of Machine Construction and Drawing 8vo, 

Weisbach's Kinematics and the Power of Transmission. (Herrmann — 
Klein.). „ 8vo, 

Machinery of Transmission and Governors. (Herrmann — Klein.). .8vo, 

Wolff's Windmill as a Prime Mover 8vo, 

Wood's Turbines 8vo, 



MATERIALS OP ENGINEERING. 

* Bovey's Strength of Materials and Theory of Structures 8vo, 7 50* 

Burr's Elasticity and Resistance of the Materials of Engineering. 6th Edition. 

Reset 8vo, 

Church's Mechanics of Engineering. . , . . , 8vo, 

* Greene's Structural Mechanics . .' 8vo, 

Johnson's Materials of Construction 8vo, 

Keep's Cast Iron. 8vo, 

Lanza's Applied Mechanics 8vo, 

Martens's Handbook on Testing Materials. (Henning.) 8vo, 

Maurer's Technical Mechanics ■ 8vo, 

Merriman's Mechanics of Materials 8vo, 

Strength of Materials i2mo, 

Metcalf's Steel. A manual for Steel-users i2mo, 

Sabin's Industrial and Artistic Technology of Paints and Varnish. 8vo, 

Smith's Materials of Machines i2mo, 

Thurston's Materials of Engineering 3 vols., 8vo, 

Part II. Iron and Steel 8vo, 

Part III. A Treatise on Brasses, Bronzes, and Other Alloys and their 

Constituents 8vo, 

Text-book of the Materials of Construction 8vo, 

Wood's (De V.) Treatise on the Resistance of Materials and an Appendix on 

the Preservation of Timber 8vo, 

Elements of Analytical Mechanics 8vo> 

Wood's (M. P.) Rustless Coatings: Corrosion and Electrolysis of Iron and 

Steel. 8vo, 4 oo> 



STEAM-ENGINES AND BOILERS. 

Berry's Temperature-entropy Diagram i2mo, 1 25 

Carnot's Reflections on the Motive Power of Heat. (Thurston.). , . . . i2mo, 1 50 

Dawson's "Engineering" and Electric Traction Pocket-book. . . .i6mo mor., 5 00 

Ford's Boiler Making for Boiler Makers i8mo, 1 00 

Goss's Locomotive Sparks 8vo, 2 00 

Hemenway's Indicator Practice and Steam-engine Economy i2mo, 2 00 

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Button's Mechanical Engineering of Power Plants 8vo, 

Heat and Heat-engines 8vo. 

Kent's Steam boiler Economy 8vo, 

Xneass's Practice and Theory of the Injector 8vo, 

MacCord's Slide-valves • 8vo, 

Mever's Modern Locomotive Construction 4to, 

Peabody's Manual of the Steam-engine Indicator f2mo. 

Tables of the Properties of Saturated Steam and Other Vapors 8vo, 

Thermodynamics of the Steam-engine and Other Heat-engines, 8vo, 

Valve-gears for Steam-engines m 8vo, 

Peabody and Miller's Steam-boi:ers 8vo, 

Pray's Twenty Years with the Indicator Large 8vo, 

Pupin's Thermodynamics of Reversible Cycles in Gases and Saturated Vapors. 

(Osterberg.). i2mo, 

Reagan's Locomotives: Simple Compound, and Electric i2mo, 

Rontgen's Principles of Thermodynamics. (Du Bois.). 8vo, 

Sinclair's Locomotive Engine Running and Management i2mo, 

Smart's Handbook of Engineering Laboratory Practice i2mo, 

Snow's Steam-boiler Practice. . . . 8vo, 

Spangler's Valve-gears 8vo, 

Notes on Thermodynamics i2mo, 

Spangler, Greene, and Marshall's Elements of Steam-engineering 8vo, 

Thomas's Steam-turbines 8vo, 

Thurston's Handy Tables 8vo, 

Manual of the Steam-engine 2 vols., 8vo, 

Part I. History, Structure, and Theory 8vo, 

Part II. Design, Construction, and Operation 8vo, 

Handbook of Engine and Boiler Trials, and the Use of the Indicator and 

the Prony Brake 8vo, 

Stationary Steam-engines 8vo, 

Steam-boiler Explosions in Theory and in Practice i2mo, 

Manual of Steam-boilers, their Designs, Construction, and Operation 8vo, 

Wehrenfenning's Analysis and Softening of Boiler Feed-water (Patterson) 8vo, 

Weisbach's Heat, Steam, and Steam-engines. (Du Bois.) 8vo, 

Whitham's Steam-engine Design 8vo, 

Wood's Thermodynamics, Heat Motors, and Refrigerating Machines. . .8vo, 



MECHANICS AND MACHINERY. 

Barr's Kinematics of Machinery 8vo, 

* Bovey's Strength of Materials and Theory of Structures 8vo, 

Chase's The Art of Pattern-making. , i2mo, 

Church's Mechanics of Engineering 8vo, 

Notes and Examples in Mechanics 8vo, 

Compton's First Lessons in Metal- working i2mo, 

Compton and De Groodt's The Speed Lathe '. nmo, 

Cromwell's Treatise on Toothed Gearing i2mo, 

Treatise on Belts and Pulleys 121110, 

Dana's Text-book of Elementary Mechanics for Colleges and Schools. .i2mo, 

Dingey's Machinery Pattern Making i2mo, 

Dredge's Record of the Transportation Exhibits Building of the World's 

Columbian Exposition of 1893. 4to half morocco, 5 00 

u Bois's Elementary Principles of Mechanics • 

Vol. I. Kinematics. . 8vo, 

Vol. H. Statics 8vo, 

Mechanics of Engineering. Vol. I. Small 4to, 

Vol. H Small 4to, 

-Durley's Kinematics of Machines. . . 8vo, 

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Fitzgerald's Boston Machinist i6mo f 

Flather's Dynamometers, and the Measurement of Power nmo, 

Rope Driving. nmo, 

Goss's Locomotive Sparks 8vo, 

* Greene's Structural Mechanics 8vo, 

Hall's Car Lubrication nmo, 

Holly's Art of Saw Filing. . . i8mo, 

James's Kinematics of a Point and the Rational Mechanics of a Particle. 

Small 8vo, 

* Johnson's (W. W.) Theoretical Mechanics i2mo, 

Johnson's (L. J.) Statics by Graphic and Algebraic Methods , . . .8vo, 

Jones's Machine Design: 

Part I. Kinematics of Machinery ... 8vo, 

"Part II. Form, Strength, and Proportions of Parts. .8vo, 

Kerr's Power and Power Transmission. 8vo, 

Lanza's Applied Mechanics 8vo, 

Leonard's Machine Shop, Tools, and Methods 8vo, 

* Lorenz's Modern Refrigerating Machinery. (Pope, Haven, and Dean.) .8vo, 
MacCord's Kinematics; or. Practical Mechanism 8vo, 

Velocity Diagrams. . . „ 8vo, 

* Martin's Text Book on Mechanics, Vol. I, Statics. i2mo, 

Maurer's Technical Mechanics 8vo, 

Merriman's Mechanics of Materials 8vo, 

* Elements of Mechanics i2mo, 

* Michie's Elements of Analytical Mechanics. . 8vo, 

* Parshall and Hobart's Electric Machine Design 4to, half morocco, 

Reagan's Locomotives Simple, Compound, and Electric i2mo, 

Reid's Course in Mechanical Drawing. , 8vo, 

Text-book of Mechanical Drawing and Elementary Machine Design. 8vo, 

Richards's Compressed Air i2mo, 

Robinson's Principles of Mechanism. , 8vo, 

Ryan, Norris, and Hoxie's Electrical Machinery. Vol. 1 8vo, 

Sanborn's Mechanics : Problems Large i2mo, 

Schwamb and Merrill's Elements of Mechanism. . , 8vo, 

Sinclair's Locomotive-engine Running and Management i2mo, 

Smith's (O.) Press-working of Metals . . 8vo, 

Smith's (A. W.) Materials of Machines i2mo, 

Smith (A. W.) and Marx's Machine Design 8vo, 

Spanglsr, Greene, and Marshall's Elements of Steam-engineering 8vo, 

Thurston's Treatise on Friction and Lost Work in Machinery and Mill 
Work 8vo, 

Animal as a Machine and Prime Motor, and the Laws of Energetics. 1 2mo , 

Warren's Elements of Machine Construction and Drawing 8vo, 

Weisbach's Kinematics and Power of Transmission. (Herrmann — Klein.) . 8vo, 

Machinery of Transmission and Governors. (Herrmann — K 1 -ein.).8vo, 
Wood's Elements of Analytical Mechanics 8vo, 

Principles of Elementary Mechanics i2mo, 

Turbines 8vo, 

The World's Columbian Exposition of 1893 4to, 



METALLURGY. 

Egleston's Metallurgy of Silver, Gold, and Mercury: 

Vol. I. Silver 8vo, 7 50 

Vol. II. Gold and Mercury 8vo, 7 50 

Goesel's Minerals and Metals' a Reference Book i6mo, mor. 3 00 

** Iles's Lead-smelting. (Postage p cents additional.) i2mo, 2 50 

Keep's Cast Iron 8vo, 2 50 

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00 



Kunhardt's Practice of Ore Dressing in Europe. . 8vo, 

Le Ch^telier's High-temperature Measurements. (Boudouard — Burgess. )i2mo. 

Metcalf's Steel. A Manual for Steel-users 12210, 

Miller's Cyanide Process i2mo, 

Minet's Production of Aluminum and its Industrial Use. (Waldo.). . . . i2mo, 

Robine and Lenglen's Cyanide Industry. (Le Clerc). . , 8vo, 

Smith's Materials of Machines i2mo, 

Thurston's Materials of Engineering. In Three Parts 8vo, 

Part II. Iron and Steel 8vo, 

Part III. A Treatise on Brasses, Bronzes, and Other Alloys and their 

Constituents 8vo, 

Ulke's Modern Electrolytic Copper Refining '. 8vo, 



MINERALOGY. 

Barringer's Description of Minerals of Commercial Value. Oblong, morocco, 

Boyd's Resources of Southwest Virginia 8vo, 

Map of Southwest Virignia Pocket-book form. 

Brush's Manual of Determinative Mineralogy. (Penfield.) 8vo, 

Chester's Catalogue of Minerals 8vo, paper, 

Cloth, 

Dictionary of the Names of Minerals •. 8vo 

Dana's System of Mineralogy Large 8vo, half leather 

First Appendix to Dana's New " System of Mineralogy." Large 8vo, 

Text-book of Mineralogy .8vo, 

Minerals and How to Study Them i2mo, 

Catalogue of American Localities of Minerals . .Large 8vo, 

Manual of Mineralogy and Petrography i2mo 

Douglas's Untechnical Addresses on Technical Subjects i2mo, 

Eakle's Mineral Tables 8vo, 

Egleston's Catalogue of Minerals and Synonyms. 8vo, 

Goesel's Minerals and Metals : A Reference Book i6mo, mor.. 

Groth's Introduction to Chemical Crystallography (Marshall) i2mo, 

Hussak's The Determination of Rock-forming Minerals. ( Smith.). Small 8vo, 
Merrill's Non-metallic Minerals- Their Occurrence and Uses. . . 8vo, 

* Penfield's Notes on Determinative Mineralogy and Record of Mineral Tests. 

8vo, paper, 50 
Rosenbusch's Microscopical Physiography of the Rock-making Minerals. 

(Iddings.). . 8vo, 5 oo 

* Tillman's Text-book of Important Minerals and Rocks 8vo, 2 00 



MINING. 

Beard's Ventilation of Mines i2mo, 2 50 

Boyd's Resources of Southwest Virginia 8vo, 3 00 

Map of Southwest Virginia. , Pocket-book form, 2 00 

Douglas's Untechnical Addresses on Technical Subjects i2mo, 1 00 

* Drinker's Tunneling, Explosive Compounds, and Rock Drills. .4to,hf. mor., 25 00 

Eissler's Modern High Explosives. ... 8~-> 4 ^o 

Goesel's Minerals and Metals ■ A Reference Book i6mo, mor. 3 oo> 

Goodyear's Coal-mines of the Western Coast of the United States i2mo, 2 50 

Ihlseng's Manual of Mining 8vo, 5 00 

** Iles's Lead-smelting. (Postage 9c. additional.). i2mo, 2 50 

Kunhardt's Practice of Ore Dressing in Europe. . '. 8vo, 1 50 

Miller's Cyanide Process i2mo, 1 oo> 

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tVDriscolPs Notes on the Treatment of Gold Ores 8vo, 

Robine and Lenglen's Cyanide Industry. (Le Clerc.) 8vo, 

* Walke's Lectures on Explosives t . 8vo, 

"Weaver's Military Explosives 8vo, 

Wilson's Cyanide Processes i2mo, 

Chlorination Process nmo, 

Hydraulic and Placer Mining i2mo, 

Treatise on Practical and Theoretical Mine Ventilation T2mo, 



SANITARY SCIENCE. 

fiashore's Sanitation of a Country House i2mo, 

* Outlines of Practical Sanitation i2mo, 

Folwell's Sewerage. (Designing, Construction, and Maintenance.) 8vo, 

Water-supply Engineering 8vo, 

Fowler's Sewage Works Analyses 121110, 

Euertes's Water and Public Health nmo, 

Water-filtration Works i2mo, 

Gerhard's Guide to Sanitary House-inspection i6mo, 

Goodrich's Economic Disposal of Town's Refuse Demy 8vo, 

Hazen's Filtration of Public Water-supplies 8vo, 

Leach's The Inspection and Analysis of Food with Special Reference to State 

Control '. 8vo, 

Mason's Water-supply. (Considered principally from a Sanitary Standpoint) 8vo, 

Examination of Water. (Chemical and Bacteriological.) i2mo, 

Ogden's Sewer Design iimo, 

Prescott and Winslow's Elements of Water Bacteriology, with Special Refer- 
ence to Sanitary Water Analysis i2mo, 

•* Price's Handbook on Sanitation. , i2mo, 

Richards's Cost of Food. A Study in Dietaries i2mo, 

Costtof Living as Modified by Sanitary Science i2mo, 

Cost of Shelter i2mo, 

Richards and Woodman's Air, Water, and Food from a Sanitary Stand- 
point 8vo, 

* Richards and Williams's The Dietary Computer 8vo, 

RideaFs Sewage and Bacterial Purification of Sewage 8vo, 

Turneaure and Russell's Public Water-supplies 8vo, 

Von Behring's Suppression of Tuberculosis. (Bolduan.) 121110, 

Whipple's Microscopy of Drinking-water 8vo, 

Winton's Microscopy of Vegetable Foods 8vo, 

Woodhull's Notes on Military Hygiene i6mo, 

* Personal Hygiene i2mo, 



MISCELLANEOUS. 

De Fursac's Manual of Psychiatry. (Rosanoff and Collins.). . . .Large i2mo, 

Ehrlich's Collected Studies on Immunity (Bolduan) 8vo, 

Emmons's Geological Guide-book of the Rocky Mountain Excursion of the 

International Congress of Geologists Large 8vo, 

Ferrel's Popular Treatise on the Winds 8vo, 

Haines's American Railway Management i2mo, 

Mott's Fallacy of the Present Theory of Sound i6mo, 

Ricketts's History of Rensselaer Polytechnic Institute, 1 824-1 894.. Small 8 vo, 

Rostoski's Serum Diagnosis. (Bolduan.) i2mo , 

Hotherham's Emphasized New Testament c Large 8vo, 

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Steel's Treatise on the Diseases or the Dog 8vo, 3 50 

The World's Columbian Exposition of 1893 410, 1 00 

Von Behring's Suppression of Tuberculosis. (Bolduan.) i2mo, 1 00 

Winslow's Elements of Applied Microscopy i2mo, 1 50 

Worcester and Atkinson. Small Hospitals, Establishment and Maintenance; 

Suggestions for Hospital Architecture: Plans for Small Hospital. 1 2mo, 1 25 



HEBREW AND CHALDEE TEXT-BOOKS. 



Green's Elementary Hebrew Grammar i2mo, 1 25 

Hebrew Chrestomathy . .8vo, 2 00 

Gesenius's Hebrew and Chaldee Lexicon to the Old Testament Scriptures. 

(Tregelles.) Small 4to, half morocco, 5 00 

Letteris's Hebrew Bible 8vo, 2 25 

19 



MAR 141907 






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